Systems, devices and apparatuses for bony fixation and disk repair and replacement methods related thereto

ABSTRACT

The present invention features new methods, apparatuses and devices for fixing adjacent bone segments, segments of a bony structure and adjacent vertebrate of a spine. The methods, apparatuses and devices utilize an apparatus for forming a channel in a surface of the bone or bony structure segments or adjacent vertebra or a channel submerged within the bone or bony structure segments or adjacent vertebra. In more particular embodiments such apparatuses and methods including forming an arcuate channel and which channel can receive therein a curved rod or implant member. Also featured are systems, apparatuses and methods for removably suspending a spacer in the intervertebral space while forming such a channel as well as systems, apparatuses and methods for use of dynamized implant members.

This application is a divisional of U.S. patent application Ser. No.12/087,912 filed Jun. 2, 2010, which is a National Stage Entry ofPCT/US2007/001402 filed on Jan. 17, 2007, which claims the benefit ofU.S. Provisional Application Ser. No. 60/759,718 filed Jan. 17, 2006.

The Ser. No. 12/087,912 application is a continuation-in-part of U.S.application Ser. No. 10/968,867 filed Oct. 18, 2004, which applicationclaims the benefit of U.S. Provisional Application Ser. No. 60/512,134filed Oct. 17, 2003. This application also is a continuation-in-part ofU.S. application Ser. No. 10/601,014 filed Jun. 20, 2003, whichapplication is a continuation of U.S. application Ser. No. 09/536,732filed Mar. 28, 2000 (U.S. Pat. No. 6,607,530), which application claimsthe benefit of U.S. Provisional Application Ser. No. 60/133,356 filedMay 10, 1999. The teachings of all of the foregoing are incorporatedherein by reference.

FIELD OF INVENTION

The present invention generally relates to methods, systems andapparatuses for bony fixation and more particularly to methods, systemsand apparatuses adapted for fixing the bones of the spine. The presentinvention also generally relates to methods, systems and devices foraugmenting, repairing or replacing the nucleus and/or annulus of anintervertebral disk of a spine, such as the spine of a mammalian body.

BACKGROUND OF THE INVENTION

Fixation or fusion of vertebral columns with bone or material, rods orplates is a common, long practiced surgical method for treating avariety of conditions. Many of the existing procedures involve the useof components that protrude outwardly, which may contact and damage abody part, such as the aorta, the vena cava, the sympathetic nerves, thelungs, the esophagus, the intestine and the ureter. Also, manyconstructions involve components that may loosen and cause undesirableproblems, often-necessitating further surgical intervention.Additionally, limiting the success of these procedures are thebiomechanical features of the spine itself, whose structure mustsimultaneously provide support to regions of the body, protect thevertebral nervous system and permit motion in multiple planes.

As indicated above, spinal surgery for spine fusion generally involvesusing implants and instrumentation to provide support to the affectedarea of the spine while allowing the bones thereof to fuse. Thetechnology initially evolved using bone chips around and on top of anarea of the spine that had been roughened to simulate a fracture in itsconsistency. The area, having encountered the bone chips, would thenproceed to heal like a fracture, incorporating the bone chips. However,surgical procedures dealing with the spine present notable challenges.For example, bioengineers have been required to identify the variouselements of the complex motions that the spine performs, and thecomponents of the complex forces it bears. This complexity has made itdifficult to achieve adequate stability and effective healing insurgical procedures directed to the spine.

One surgical technique provided by Cloward, involves cutting a doweltype hole with a saw across or through the moveable intervertebral discand replacing it with a bone graft that was harvested from the hip bone.This procedure results in a fusion of the adjacent vertebral bodies andlimits motion and mobility. However, as a result of the complex motionsof the spine, it is often difficult to secure the dowel from displacing.Further, it has become apparent over time, however, that this particulartechnique does not always yield a secure fusion.

Other techniques have been developed that involve the placement ofvarious hardware elements, including rods and hooks, rods and screws andplates and screws. The dowel technique also has advanced over the pastfive years or so, with dowels being fabricated from cadaver bone ormetals such as titanium or stainless steel. These techniques, whetherusing hardware, dowels or some combination thereof, have a common goalto enhance stability by diminishing movement, thereby resulting in orenhancing the potential of a fusion of adjacent vertebral bones. Forexample, in one of these other techniques, the disc is removed andadjacent vertebrae are positioned in a stable position by placing aplate against and traversing them, which plate is secured or anchored toeach by means of screws.

In another procedure, cages in the form of two parallel circular orrectangular devices are made out of a material such as titanium orstainless steel and these devices are fenestrated. Bone is packed in thecenter of the devices that will heal to adjacent bone through eachfenestration. In this procedure, the disc space is distracted so allligamentous structures are taut and the bones are held in their normalmaximal position of distraction. Because the cages are implanted inspongy bone, they are more likely to collapse the surrounding bone, thusresulting in loss of distraction and subsequently cage dislodgment.

U.S. Pat. No. 5,591,235 reports a certain spinal fixation device andtechnique for stabilizing vertebrae. In this technique, a hollow screwis inserted into a hole, preferably a hole saw recess, in each adjoiningvertebrae. A channel is cut into the vertebrae, which is lined up withcorresponding axial slots in the screw. A rod is inserted into thechannel and so as to pass through the axial slots in the screw. The rodis secured to each of the screws by means of a locking cap. The rod alsois arranged so as to provide a bridge between the hollow screws in theadjoining vertebrae. Certain disadvantages have been surmised using sucha device and technique. For example, it has become apparent that thetrough in the vertebral bodies destabilizes some of the cortex of thevertebrae body wall, which is the strongest component.

In addition to fixation or fusion of vertebral columns, the prior artalso describes methods or other spinal repair procedures, such asdiscectomy wherein an artificial disc or prosthetic device is placedwithin the vertebrae of the spine. For such prior art methods andrelated devices, there have been short comings such as having difficultyin securing the prostheses within the vertebral space or resulting insignificant modification or damage to the load bearing surfaces of thevertebrae in an effort to secure the prosthesis.

Another method or other spinal repair technique involves augmentation ofthe nucleus of an intervertebral disk of the spine. The intervertebraldisk is a flexible cartilaginous structure that is disposed betweenadjacent vertebrae. These disks form joints between the bodies of thevertebrae, which serve to unite adjacent vertebrae and to permitmovement between them. These disks also play a role as shock absorberswhen force is transmitted along the vertebral column during standing andmovement.

Each disk is formed of two parts, a central mass called the nucleuspulpsous (herein the nucleus) and a surrounding fibrous layer, theannulus fibrosus (herein the annulus). The nucleus has a semi-gelatinousconsistency, which allows it to become deformed when pressure is placedupon it, enabling the disk to change shape as the vertebral columnmoves.

There is described in U.S. Pat. Nos. 5,047,055; 5,824,093 6,264,695; theteachings of which are incorporated herein by references, varioustechniques and/or prosthetics for use in replacing or augmenting aspinal disc nucleus. Given the structure of the disk and its locationbetween adjacent vertebrae, it is not s simple task to access thenucleus for the insertion of such prosthetics or materials to augmentthe nucleus. One technique for accessing the nucleus contemplates usingthe defect in the annulus, however, in practice the defect usually needsto be enlarged to allow the insertion of the prosthetic. Anothertechnique contemplates having the surgeon drill through one of theadjacent bodies using a lateral approach. This another technique reliesheavily on the skill and dexterity of the surgeon not to damagesurrounding tissues, nerves and blood vessels. Also, the holed formed bysuch drilling is not easily sealed because of its shape andconfiguration.

Conventional techniques relating to fixation of the spine and bonystructure rely in great part on the skill and dexterity of the surgeonto control the devices and instrumentalities being used to protectsurrounding tissues, muscles, nerves and blood vessels from damageduring the procedure. This is so because the devices and/orinstrumentalities that the surgeon uses during such techniques,themselves do not provided the surgeon with a mechanism to protect thetissues, muscles, nerves and blood vessels surrounding the treatment ortarget area within the body from coming into contact with the device orinstrumentality during the procedure. Consequently, the surgeon must usesurgical techniques to relocate tissues, muscles, nerves and bloodvessels from the surgical field, if that is possible, and for thosewhich it is not possible, the surgeon must take care in the use of thedevice or instrumentality to prevent injury. It should be recognizedthat the surgeon while inserting and retracting or removing the deviceor instrumentality from the bony structure or spine must exercise suchcare to prevent injury.

Thus, it would be desirable to provide a new apparatus, system andmethods for bony fixation that enhances healing of the bone whileproviding structural support therefore. It would be particularlydesirable to provide such an apparatus, system and method that wouldinvolve the use of open surgical or minimally invasive surgicaltechniques as well as a technique in which the implant burrows in thestructure of the bone; more particularly a technique in which theimplant burrows in the bone spine, traverses across the disk space, andends in an adjacent or neighboring vertebrae or vertebras, providinglimited or no protrusions. It also would be desirable to provide such anapparatus, system and method where the implant is retained within thebone without requiring external fixation including contour-varyingexternal vertebral wall fixation as compared to conventional devices, assuch a device would avoid many of the problems associated withconventional devices such as blood vessel injury, erosion into organs,as well as placement near nerves. It also would be desirable for suchapparatuses and systems to be adaptable for use in a wide range ofprocedures and techniques, including but not limited to augmentation ofthe nucleus such as by use of prosthetics.

SUMMARY OF THE INVENTION

The present invention features new methods, apparatuses and devices forfixing adjacent bone segments, segments of a bony structure and adjacentvertebrate of a spine. The methods, apparatuses and devices utilize anew apparatus for forming a channel in a surface of the bone or bonystructure segments or adjacent vertebra or a channel submerged withinthe bone or bony structure segments or adjacent vertebra. In moreparticular embodiments such apparatuses and methods include forming anarcuate channel. Also the channel formed can receive therein a curvedrod or implant member, which also preferably is arcuate, and avoids theassociated problems with prior cage or straight rod and screw systems.Also featured are devices used in connection with such apparatuses andmethods.

According to an aspect of the present invention there is featured amethod for forming a channel, an arcuate channel in adjacent bonesegments, adjacent segments of a bony structure or adjacent vertebra ofa spine, the bone segments, bony structure and spine more particularlybeing those of a mammalian body (e.g., human body). Such a methodincludes positioning a frame assembly proximal the treatment or surgicalsite, securing the frame assembly to the adjacent segments of the boneor bony structure or adjacent vertebra and rotating a drill bit in fixedrelation to the frame assembly to form the channel in the surface orsub-surface of the bone, bony structure or vertebra. In furtherembodiments, the method further includes mechanically engaging asecuring mechanism to the frame assembly so that the frame is maintainedin fixed relation by such mechanical engagement alone or in combinationwith the lateral stiffness of the securing mechanism.

In more specific embodiments, the frame assembly includes a frame havinga plurality of through apertures, each through aperture including aconstricted portion and a plurality of securing members. Each of theplurality of securing members are driven through the through aperturesand the constricted portion and into the bone, bony structure orvertebra at the site such that the frame is secured in fixed relation tothe bone, bony segments or vertebra by the engagement of the constrictedportion with the securing member and by the lateral stiffness of thesecuring members.

In further embodiments, the method further includes attaching a drillassembly to the frame assembly so a drill bit of the drill assemblyfollows a predetermined path, more particular a predetermined circularpath, in fixed relation with respect to the frame and moving the drillbit through the predetermined path while the drill bit is rotating so asto cut the channel. In more particular embodiments, the method furtherincludes providing a pivot arm assembly having a pivot arm that rotatesin fixed relation to the frame, securing a portion of the drill assemblyincluding the drill bit to the pivot arm assembly and rotating the drillbit using the pivot arm assembly so the drill bit traverses thepredetermined path, more specifically the predetermined circular path.

Such a method further includes determining if the rotation of the drillbit in a first direction formed a complete channel or a partial channeland in the case where it is determined that a partial channel wasformed, reconfiguring the drill assembly so as to be rotatable in asecond rotational direction that is different from the first directionand rotating the drill bit in the second rotational direction to formthe complete channel.

Such methods further include locating and attaching an implant in thechannel so formed and securing the implant therein using any of a numberof techniques known to those skilled in the art. In more particularembodiments, such a method include securing the implant to the bone,bony structure or vertebra using a plurality or more of securingdevices, more specifically using a plurality of threaded members.

Such methods further include forming a plurality or more channels in oneor more surfaces of the bone or bony structure segments or adjacentvertebra or a channel submerged within the bone or bony structuresegments or adjacent vertebra. In particular embodiments, two channelsare formed submerged within the bone or bony structure segments oradjacent vertebra. In further embodiments, such methods include locatingan implant in each of the plurality or more channels so formed andsecuring the implant therein using any of a number of techniques knownto those skilled in the art. In more particular embodiments, suchmethods include securing the implant to the bone, bony structure orvertebra using a plurality or more of securing devices, morespecifically using a plurality of threaded members. It should be notedthat the term adjacent vertebrae includes the sacrum.

In further embodiments, such implants include a sliding implant devicecomprising two implant members, one of which is disposed in slidingrelation with respect to the other. Thus, such methods further includeimplanting the sliding implant device such that one member is securablyretained to, or within, one of the adjacent vertebrae; such that theother member is securably retained to, or within, the other of theadjacent vertebrae; and such that the sliding interconnection betweenthe two members is located in the intravertebral space between theadjacent vertebrae.

In further embodiments, the two implant members also are configured soas to include stops, elements or surface artifacts in opposing surfacesof the two members that cooperate so as to restrain further relativemovement between the two members. More particularly, such stops,elements or surface artifacts are arranged so as to prevent the twomembers from be displaced in a direction that would allow the said onemember to slide out an end of said other member, thereby breaking thesliding interconnection between the two members. In illustrativeembodiments, each such stop comprises a vertically extending member thatextends upwardly from each of the opposing surfaces and which extends atleast partially about the circumference of each member.

In further embodiments, such implants include a dynamized implant devicecomprising two implant members and a compressive segment compressiblyinterconnecting the two implant members. Thus, such methods furtherinclude implanting the dynamized implant device such that one member issecurably retained to, or within, one of the adjacent vertebrae; suchthat the other member is securably retained to, or within, the other ofthe adjacent vertebrae; and such that the compressive segment is locatedin the intravertebral space between the adjacent vertebrae. Inparticular embodiments, the compressive segment further includes aresilient element or feature (e.g., spring or compressible material)that in effect controls or limits the amount of compression or movementbetween the two members.

According to further aspects of the present invention there is featureda method for forming a channel, an arcuate channel in adjacent vertebraof a lower portion of the spine, more particularly between the lumbarvertebrae and more specifically, between the lowest lumbar vertebrae(L-5) and the sacrum. Such a method includes positioning a frameassembly proximal the treatment or surgical site, securing the frameassembly to the adjacent segments of the adjacent vertebra including thelumbar vertebrae L-5 and the sacrum and rotating a drill bit in fixedrelation to the frame assembly to form the channel in the surface orsub-surface of the bone, bony structure or vertebra. In furtherembodiments, the method further includes mechanically engaging asecuring mechanism to the frame assembly so that the frame is maintainedin fixed relation by such mechanical engagement alone or in combinationwith the lateral stiffness of the securing mechanism.

In further embodiments, the provided frame assembly is configured toaccommodate relative differences in the surface and the height orelevation between the adjacent vertebrae including the lumbar vertebraeL-5 and the sacrum so the channel being formed follows a desired paththrough the adjacent vertebrae. In more particular embodiments, aportion of the frame assembly is configured so the pivot point of therotating drill point is in fixed relation with respect to the desiredpath.

According to further aspects, such methods further includes removablyattaching a spacer element to the frame assembly so as to maintainalignment of the spacer with respect to the frame as well as withrespect to the channel being formed in adjacent vertebrae and releasingthe spacer element from the frame assembly following forming of thechannel in the adjacent vertebrae using any of the methods describedherein. In one embodiment, the spacer element includes a preformedaperture and said attaching includes attaching the spacer element to theframe assembly so as to maintain alignment of the preformed aperturewith respect to the frame as well as with respect to the channel beingformed in adjacent vertebrae. In another embodiment, said methodincludes forming an aperture in the spacer element, preferably whenforming the channel in the adjacent vertebrae. Such spacers can beformed from any of a number of materials, including bone, metal,allograft or autologous as well as using any of a number of techniquesknown to those skilled in the art. It also is contemplated that suchspacers remain in the intervertebral disc space following the procedurebeing performed that embodies the methodologies of the present inventionas well as devices, apparatuses and systems of the present invention.

Also featured is a system or apparatus embodying the frame, pivot armassembly and drill assembly herein described. In addition there isfeatured devices or tools for use with such systems, apparatuses andmethods to drive the securing members or the remove the securing membersafter the channel has been formed in the surface or sub-surface of thebone, bony structure or adjacent vertebras.

In further aspects of the present invention, there are featured systems,apparatuses and methods for augmenting, repairing or replacing thenucleus and/or the annulus that embody the frame, pivot arm assembly anddrill assembly herein described as well as other such systems andapparatuses described in U.S. Pat. No. 6,607,530 and U.S. Ser. No.10/019,265 (the teachings of which are incorporated herein byreference). In such systems, apparatuses and methods, the drill isrotated as described herein to form a channel or passage through one ofthe vertebrae that is adjacent to the disk to be repaired so that thenucleus of the disk can be accessed through the vertebral end plate. Thesize of the channel or passage formed can be controlled so as to providethe desired or needed amount of access for the surgeon to insert forexample, the material or prosthetic into the nucleus as well as otherdevices or mechanisms (e.g., a patch) that can be used to form a seal orclosure at the defect on the annulus. Such control is achieved forexample, by adjusting the size of the drill bit to fit a givenapplication. Such a disk repair procedure also can include sealing ofthe channel, passage or hole formed in the vertebrae using any of anumber of techniques known to those skilled in the art, such as forexample, inserting bone or bony material into the channel.

It should be recognized that the drilling apparatus, methods and systemsof the present invention can be used anteriorally or posteriorally andso that the drill bit of such systems or apparatuses can penetrate orenter the vertebral body through the pedicles.

Other aspects and embodiments of the invention are discussed below.

BRIEF DESCRIPTION OF THE DRAWING

For a fuller understanding of the nature and desired objects of thepresent invention, reference is made to the following detaileddescription taken in conjunction with the accompanying drawing figureswherein like reference character denote corresponding parts throughoutthe several views and wherein:

FIG. 1 is a side view of a drilling apparatus according to an aspect ofthe present invention;

FIG. 2 is one perspective view of the drilling apparatus of FIG. 1;

FIG. 3 is another perspective view of the drilling apparatus of FIG. 1;

FIGS. 4A,B are various perspective views of the pivot arm assembly ofthe drilling apparatus of FIG. 1;

FIG. 5 is a perspective view of the pivot arm of the pivot arm assembly;

FIG. 6 is a perspective view of the drill assembly of the drillingapparatus and a drive motor connected thereto;

FIG. 7 is a cross-sectional side view of the drill assembly of FIG. 6;

FIG. 8 is a side view of the bit, bearing and drive cable sub-assemblyof the drill assembly;

FIG. 9 is a cross-sectional view of the drill assembly end including thebit, illustrating another exemplary bit;

FIG. 10A is a side view of a nail removal tool according to oneembodiment of the present invention;

FIG. 10B is an end view of the nail removal tool;

FIG. 11 is a perspective view of the nail removal tool mounted on theplatform assembly of the drilling apparatus;

FIG. 12 is a side view with a partial cut away of a nail drive toolaccording to an embodiment of the present invention;

FIGS. 13A-L are illustrations of the process for forming a recess inadjacent vertebral bodies;

FIGS. 14A-D are illustrations of the process for implanting or attachinga curved rod across the adjacent vertebrae;

FIGS. 15A-H are illustrations of the process for forming a throughaperture in adjacent vertebral bodies;

FIG. 15I is an illustrative view of adjacent vertebral bodiesillustrating the fixed cutting depth aspect yielded by the drillingapparatus of the present invention;

FIGS. 16A-C are illustrations of the process for implanting or attachinga curved rod in the through aperture and across the adjacent vertebrae;

FIG. 17 is a side view of a drilling apparatus according to anotheraspect of the present invention illustrated disposed upon adjacentvertebral bodies;

FIG. 18A is a perspective view of drilling apparatus according to yetanother aspect of the present invention;

FIG. 18B is side view of the drilling apparatus of FIG. 18A;

FIG. 18C is another perspective view from a different perspective of thedrilling apparatus of FIG. 18A;

FIG. 19A is a perspective view of a portion of a spine on which ismounted a drilling apparatus of the present invention for creating achannel, passage or hole for a disk repair procedure;

FIG. 19B is a perspective view of the portion of the spine illustratingthe channel, passage or hole through an adjacent vertebrae allowingaccess to the nucleus;

FIG. 20 is a flow diagram briefly describing a disk repair procedureaccording to the present invention;

FIGS. 21A,B are side views of a drilling apparatus according to anotheraspect of the present invention where FIG. 21B includes a partialcutaway;

FIG. 21C is a perspective view of a lower portion of a spine includingthe sacrum on which is mounted a drilling apparatus of FIG. 21A,B;

FIG. 22A is a cross-sectional side view that illustrates implanting orattaching a sliding implant device in the through apertures and acrossthe adjacent vertebrae;

FIG. 22B is a detailed view of sliding connection of the sliding implantdevice of FIG. 23A;

FIG. 23A is a cross-sectional side view that illustrates implanting orattaching a compressible implant device of the present invention in thethrough apertures and across the adjacent vertebrae;

FIGS. 23B-C are illustrations of embodiments of the compressive segmentfor a compressible implant device of the present invention;

FIG. 24A illustrates implanting or attaching two curved implants in thethrough apertures and across the adjacent vertebrae;

FIG. 24B is a cross-sectional side view of the implants within andacross the adjacent vertebrae of FIG. 22A;

FIG. 24C is a lateral view of the spine showing an illustrativeembodiment of stacked overlaid implant devices or arcuate rods inmultiple adjacent vertebrae;

FIG. 24D is an anterior view of the crossing point of adjacent implantdevices;

FIG. 24E is a lateral view of the spine showing another illustrativeembodiment of stacked overlaid implant devices or arcuate rods inmultiple adjacent vertebrae;

FIGS. 25A,B are top and side views respectively of an illustrative frameaccording to another aspect of the present invention;

FIG. 25C is a perspective view of a portion of a spine on which ismounted the illustrative frame of FIGS. 25A,B;

FIG. 26A is a top view of an embodiment of the illustrative frameaccording to said another aspect of the present invention;

FIG. 26B is a perspective view of a portion of a spine on which ismounted the illustrative frame of FIG. 26A;

FIGS. 27A-C are top, side and cross-sectional end views respectively ofanother embodiment of the illustrative frame according to said anotheraspect of the present invention;

FIG. 28A is an illustrative view of a drilling apparatus includinganother embodiment of the illustrative frame according to another aspectof the present invention when mounted upon adjacent vertebral bodies;

FIG. 28B is a cross-sectional end view of the illustrative frame of FIG.28A;

FIG. 29A is an illustrative view of another drilling apparatus includinganother embodiment of the illustrative frame according to another aspectof the present invention when mounted upon adjacent vertebral bodies;

FIG. 29B is a cross-sectional end view of the illustrative frame of FIG.29A; and

FIGS. 30A-C are views of various illustrative embodiments of securing anarcuate rod or implant device within a spacer;

FIG. 31 is an illustrative view of adjacent vertebral bodiesillustrating an implanted arcuate rod or implant device and piningmember to secure an intervetebral spacer or cage (not shown) to andbetween the adjacent vertebral bodies;

FIGS. 32A,B are various illustrative views of an arcuate rod or implantdevice, cap and screw assembly according to one illustrative embodimentof the present invention, where the arcuate rod or implant device isshown in cross-section;

FIG. 32C is an illustrative view of an arcuate rod or implant device,cap and screw assembly according to another illustrative embodiment ofthe present invention, where the arcuate rod or implant device is shownin cross-section;

FIGS. 33A-D are top, bottom and side views respectively of oneillustrative embodiment of a cap according to the present invention;

FIG. 33E is a cross-section view along section L-L of FIG. 33A;

FIG. 33F is a cross-section view along section R-R of FIG. 33B;

FIGS. 34A-B and F-G are top, bottom and side views respectively ofsecond illustrative embodiment of a cap according to the presentinvention;

FIG. 34C is a cross-section view along section M-M of FIG. 33A;

FIG. 34D is a cross-section view along section L-L of FIG. 34A;

FIG. 34E is a cross-section view along section R-R of FIG. 34B; and

FIGS. 35A-B are various illustrative axonometric views of adjacentvertebral bodies illustrating yet an arcuate rod or implant device, capand screw assembly according to yet another illustrative embodiment ofthe present invention, where the arcuate rod or implant device is shownin cross-section.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now to the various figures of the drawing wherein likereference characters refer to like parts, there is shown in FIGS. 1-3various views of a drilling apparatus 100 according to an aspect of thepresent invention that is generally comprised of a platform assembly200, a pivot arm assembly 300 and drill assembly 400. As hereinafterdescribed in more detail, the pivot arm assembly 300 is removablysecured to the platform assembly 200 and the platform assembly isremovably secured to the bone or bony structure so as to maintain thepivot point of the pivot arm assembly in general fixed relation to thebone or bony structure. The drill assembly 400 is removably secured tothe pivot arm assembly 300 so as to maintain the end of the drillassembly including the bit 410 or drill end in fixed relation withrespect to the pivot arm 302 of the pivot arm assembly. Consequently, asthe pivot arm 302 is rotated about the pivot point, the bit 410 followsa predetermined arcuate, curved or circular path in the bone or bonystructure as defined by the length of the pivot arm.

For purposes of illustrating the drilling apparatus 100 of the presentinvention, reference hereinafter is generally made to the structure andstructural features or elements of a mammalian spine (e.g., humanspine), however, this shall not be construed as limiting the use andapplication of the drilling apparatus of the present invention to theseapplications. It is contemplated and as such within the scope of thepresent invention to adapt the drilling apparatus of the presentinvention and the methods related thereto so the drilling apparatus isused so as to form grooves or arcuate passages in bones or bonystructures of the mammalian body in which grooves is received a curvedrod or other member as is hereinafter described thereby stabilizingand/supporting the bone or bony structure.

The platform assembly 200 includes a frame 202, a plurality of firstpath guards 204 and a mechanism for securing the frame to the bone orbony structure. In the illustrated embodiment, the securing mechanismcomprises a plurality of nail members 206 that each pass respectivelythrough each of the frame 202 and the first path guards and so as to bedisposed in the bone or bony structure as herein described. In furtherembodiments, and as hereinafter described, the platform assembly 200 canfurther include a second path guard 204 b, in cases where the drillingapparatus 100 is used to form a groove or recess in an outer surface ofthe bone or bony structure thereby providing a protective structurebetween the moving and rotating drill bit 410 and the tissues or otherstructures or features of the mammalian body (e.g., nerves, bloodvessels) that are proximal the bone or bony structure outer surface.

The frame 202 is configured and arranged so as to form an essentiallyrigid structure and frame work to which the pivot arm assembly 300 isremovable attached and at least one and more particularly two throughpassages 210 that communicate with a corresponding passage in the firstpath guards 204. The through passages 210 and the corresponding passagein the first path guards 204 are each configured and arranged so as toallow the outer tube member 402 of the drill assembly to pass therethrough as the pivot arm 302 is being rotated or pivoted about the pivotpoint. The frame 202 is composed of any one of number of materials knownto those skilled in the art that is appropriate for the intended use andthe anticipated structural loads that can be imposed during use. In anexemplary embodiment, the frame 202 is made from stainless steel such asa stainless steel bar stock.

The first path guards 204 are secured to the frame 202 so as to extenddownwardly from a bottom surface 210 b therefrom. Each of the first pathguards 204 are arranged so as to include a generally centrally locatedthrough passage, through which the outer tube member 402 and the drillbit 410 or burr of the drill assembly 400 are passed. In addition, eachof the first path guards 204 are configured and arranged so as toinclude a plurality of through passages 220, one for each of the nailmembers 206. Each of the nail member through passages 220 also arepreferably formed in the first guard member so as to present constrictedholes that firmly grab the nail member within the corresponding throughpassage. In this way, the gripping action of the through passages andthe lateral stiffness of the nail members 206 provides a mechanism forsupporting and fixing the frame 202, and in turn the pivot point'srelation with respect to the bone, bony structure or spine. In use, eachof the nail members 206 are passed through the through aperture 208 inthe frame 202 and driven through the through passage 220 of the firstpath guard 204.

In more particular embodiments, each through passage 220 is configuredand arranged so that the passages are over sized with respect to thediameter of the nail members 206 and a portion of the through passageforms a land or raised region comprising a constriction region. Moreparticularly, the constricted region is located above or from the lowerend of the through passage such that the pointed ends of each nailmember 206 are not exposed when the nail members 206 are initiallypressed into the platform assembly 200. In this way, each of the nailmembers 206 are confined within the first path guard 204 prior topositioning of the platform assembly 200 in the surgical field amidstvital structures or features of the mammalian body.

The first path guards 204 are constructed from any of a number ofmaterials known to those skilled in the art that are appropriate for theintended use and so as to provide a medium that can form a protectivebarrier between the drill path and the tissues including nerves andblood vessels that are proximal the site of the bone, bony structure orspine to be drilled. In exemplary embodiments, the first path guards 204are made form a plastic material such as, but not limited to,polycarbonate. In further embodiments, the end of the first path guard204 proximal the bone, bony structure or spine is configured andarranged so as to include a soft conformal region that contact and sealagainst the surface of the bone, bony structure or spine. Alternatively,a conformable material may be disposed in the space, if any, between thebase or bottom surface of each first path guard 204 and the opposingsurface of the bone, bony structure or spine (e.g., vertebral cortex).

The nail members 206 are configured and arranged so that each extendsfrom a top surface 210 a of the frame 200, through the frame and thefirst path guard 204 and a sufficient distance into the bone, bonystructure or spine to fix and secure the frame thereto. In addition,each of the nail members 206 also is configured and arranged so at leasta portion thereof has a diameter that is set so that this portion of thenail member is gripped within the constricted region of the throughpassage 220 of the first path guards 204 as herein described.

Each of the nail members 206 includes a head portion 230 and a shaftportion 232 one end of which is mechanically coupled to the head portionusing any of a number of techniques known to those skilled in the artthat yields a nail member that is capable of being driven into the bone,bony structure or spine and removed therefrom. In further embodiments,the nail member 206 is formed such that the head portion 230 is integralwith the shaft portion 232. In particular embodiments, the head portion230 is configured and arranged so as to allow the nail member 206 to bedriven through and into the bone, bony structure or spine and laterremoved therefrom. In further embodiments, the head portion 230 isfurther configured so as to include a through aperture or hole extendinggenerally laterally or radially through the head portion, the throughaperture being configured to receive one or more suture lines thereinfor interoperative locating.

The other end of the shaft portion 232 is configured so as to form apointed end that is appropriately configured and shaped for insertioninto the bone, bony structure or spine and for securing the pointed endand a portion of the shaft member in such bone, bony structure or spine.In illustrative embodiments, the pointed end is configured to form anon-cutting pencil point end that wedges the end into the bone, bonystructure or spine.

In the illustrated embodiment, four nail members 206 are driven througheach of the first guard members 204 and into the bone or bony structureor spine. This shall not be construed as a limitation as the number andplacement of the nail members is not so particularly limited as each endof the frame 202 can be secured to the bone or bony structure using oneor more and more particularly two or more nail members 206. It alsoshould be recognized that other mechanisms known to those skilled in theart, such as screws or threaded devices, are contemplated for use withthe present invention.

Each of the nail members 206 is composed of any one of number ofmaterials known to those skilled in the art that is appropriate for theintended use and the anticipated structural loads that can be imposedduring use. In an exemplary embodiment, the nail member 206 is made froma metal such as stainless steel.

Referring now also to FIGS. 4-5, the pivot arm assembly 300 includes aradial arm or pivot arm 302, a pivot pin bracket 304 and a pivot pin306. The pivot pin bracket 304 includes side plates 310 and finger pads312 that are secured to the side plates, where the pivot pin extendsbetween the side plates. The pivot pin 306 is received within anaperture 320 in the pivot arm such that the pivot arm can rotate about apivot axis 321.

The pivot pin bracket 304, more particularly the side plates 310thereof, is generally configured and arranged so as to secure the pivotarm assembly 300 to the platform assembly 200 so as to prevent thedisengagement of the pivot arm assembly and correspondingly the drillassembly 400 from the platform assembly when it is being rotated fromthe fully retracted position of the pivot arm. More particularly, theside plates thereof are configured and arranged such that the bracketcan be removed from the platform assembly 200 when the pivot arm is inthe fully retracted position.

In particular embodiments, the side plates 310 are configured so as toform spring members that can slide in mating grooves provided onopposing inside surfaces of the platform assembly frame 202. Inaddition, the side plates 310 further include binding head screws thatengage complimentary holes within the mating grooves to lock the pivotpin bracket 304 in place. A finger pad 312 is secured to an end of eachside plate so as to facilitate placement and removal of the pivot pinbracket 304 in the platform assembly. In illustrative embodiments, thefinger pads 312 are configured so as to include concavities 313 that thefingertips of the user can engage to thereby facilitate placement andremoval of the pivot pin bracket 304.

The pivot arm 302 is configured and arranged so an end 322 thereofincludes an aperture 320 so the pivot arm can be mounted upon the pivotpin 306 such that it can rotate or swing about the pivot pin 306. Thepivot arm 302 also is configured and arranged so as to include a matingportion 324 that receives therein and mates with a feature of the drillassembly 400 so as to removably secured the drill assembly to the pivotarm. The mating portion 324 is located distal from the end 322 of thepivot arm 302 that is mounted upon the pivot pin 306. Also, the lengthof the pivot arm 304, more particularly the distance between the pivotaxis 321 and the mating portion 324, establishes or controls the radiusof curvature of the hole or recess being formed in the bone, bonystructure or spine by the rotation of the pivot arm. It should be notedthat this radius of curvature or diameter is different from the diameterof the hole or recess formed by the rotating drill bit 410 or bur. Assuch, it is contemplated that pivot arms 302 will be provided that havelengths set that are appropriate for the given geometry and physicalmakeup of the mammalian body.

The platform assembly 200 and pivot arm assembly 300 of the presentinvention advantageously creates a mechanism that allows tissue, muscle,blood vessels (e.g., aorta) and nerves to pass under and around theplatform assembly and also to localize the drilling elements of thedrill assembly 400 within the structure of the platform assembly. Inaddition, the pivot arm assembly 300 in combination with the platformassembly provides a mechanism to control the radial movement or radialmotion of the drilling elements of the drill assembly 400 from theirinsertion into the bone or bony structure as well as the retraction fromthe bone or bony structure such that the drilling elements traverse aspecific radius of curvature during such insertion and retraction. Inthis way, the drilling apparatus of the present invention also controlsthe maximum depth within the bone or bony structure the drillingelements can attain during use. Thus, and in contrast to conventionaltechniques, devices and instrumentalities, the drilling apparatus 100 ofthe present invention provides a mechanism that protects tissues, bloodvessels and nerves from damage while the drilling elements of the drillassembly 400 are being inserted into and withdrawn from the bone or bonystructure as well as assuring that the drilling elements will follow agenerally fixed path such that the drilling elements do not come intocontact with nor damage the tissues, blood vessels and nerves proximalto and surrounding the bone or bony structure while the hole or recessis being formed in the bone or bony structure. Consequently, thedrilling apparatus 100 of the present invention minimizes the potentialfor damage without having to rely solely on the dexterity or skill ofthe surgeon, as is done with conventional techniques and devices.

In further embodiments, at least a segment or a part of the matingportion 324 is configured and arranged so as to complement the shape ofthe drive assembly feature being received therein. For example, and asillustrated, a portion or part of the key 404 of the drill assembly isconfigured so as to be polygonal in shape and the mating portion 324 isconfigured so as to include a polygonal shaped recess for receivingtherein the hexagonal surfaces of the key. Such polygonal shapesincludes but are not limited to a square, triangular, rectangular orhexagonal shapes.

In yet further embodiments, the pivot arm 302 is configured and arrangedso as to include a finger grip 326 at or proximal and end of the pivotarm that is opposite to the end 322 mounted upon the pivot pin 306. Thefinger grip 326 presents a structural element or feature that isconfigured to allow the thumb and/or fingers of the user to grasp thefinger grip so as to thereby control rotation of the pivot arm and toalso control the drilling pressure (i.e., pressure being exerted by thedrill bit 410 on the bone or bony structure while drilling the hole orrecess therein). In illustrated embodiments, the finger grip 326presents a small tab having bilateral concavities that allow the fingertips to grasp it or a through aperture.

Each of the pivot arm 302, pivot pin 306, side plates 310 and fingerpads 312 is composed of any one of number of materials known to thoseskilled in the art that is appropriate for the intended use and theanticipated structural loads that can be imposed during use. In anexemplary embodiment, any one or more of the foregoing elements of thepivot arm assembly 300 is made from a metal such as stainless steel.

Referring now also to FIGS. 6-7 there is shown a perspective view and across-sectional view of drill assembly 400 of the present invention.There also are shown in FIGS. 8-9 various views of portions or segmentsof such a drill assembly and/or embodiments thereof. The drill assembly400 generally forms a curved structure, more particularly a curvedtubular structure, that is attached to the pivot arm 302 as hereindescribed and which thus swings around the pivot point or pivot axis321. In use, the drill bit 410 rotates about its axis while this axis isheld tangent to and swept along an arc of constant radius as defined bythe distance between the mating portion 324 of the pivot arm 302 and thepivot axis 321. This movement results in or yields a toroidal hole.

The drill assembly includes an outer tube member 402, a key 404, aflexible inner housing 406, a drive cable 408, a drill bit 410 or burr,a barbed fitting 412, a drive adapter 414. In further embodiments, thedrill assembly includes a distal drive cable bearing 416 and a proximaldrive cable bearing 418. Any one of a number of motors 20 or motor driveassemblies as is known in the art having sufficient power (e.g., torque)and rotational speed are coupled to the drive adapter 414 including butnot limited to the Micro100 (Linvatech/Hall Surgical 5053-009) orBlachmax (Anspach Blackmax-KT-0). The drive adapter 414 is a swage-typeof fitting that is configured and arranged so it can be swaged upon oneend of the drive cable 408. The drive adapter 414 also is configured andarranged so as to provide an input end arrangement that can bemechanically coupled to the output end of a variety of motors or motordrive assemblies or drills including those identified herein.

The outer tube member 402 is curved to a predetermined radius ofcurvature so that the centerline thereof is a set distance from thepivot axis 321 of the pivot arm 302. The key 404 and the distal cablebearing 416 are secured to the outer tube using any of a number oftechniques known to those skilled in the art that is appropriate for thematerials comprising these elements or features. In exemplaryembodiments, the key 404 and the distal cable bearing 416 are secured tothe outer tube member by brazing or soldering. In more particularembodiments, the distal drive cable bearing 416 is secured to the outertube member 402 such that the outer edge of the outer race of thebearing lies in a radial plane from the pivot point, whereby the axis ofthe drill bit 410 or burr is arranged so as to tangent to the centerlineof the arc of the outer tube member.

The key 404 is generally cylindrical in construction and serves to alignand anchor the outer tube member 401 to the pivot arm assembly 300, moreparticularly the pivot arm 302. As indicated herein, a portion 405 ofthe key 404 is configured so as to provide a surface feature, artifactor contour that complements at least a part of the mating portion 324 ofthe pivot arm. In the illustrated embodiment, the portion 405 of the key404 forms an external polygonal feature that mates to the internalpolygonal feature provided in the pivot arm mating portion. The key 404also is configured and arranged so as to be secured to the matingportion using any of a number of techniques known to those skilled inthe art. In an exemplary embodiment, a portion of the key is configuredso as to include a external thread and a part of the mating portion 324is configured so as to include a complementary threaded element orfeature in an aperture thereof. In use, the key is articulated so as tothreadably secure or lock the key 404 to the pivot arm 302. Othertechniques for securing, such as brazing, soldering and adhesives arecontemplated for use with the present invention.

The key 404 includes a through aperture that is coupled to the innerregion or area of the outer tube member 402. The diameter of the keythrough aperture and the outer tube member are set so as to at leastallow the flexible inner housing 406 and the drive cable 408 to passthere through. The flexible inner housing 406 extends from the distalend 401 of the outer tube member 402 to the barbed fitting 412. Theflexible inner housing 406 is a generally tubular member of flexibleconstruction, such as Teflon for example, for housing the drive cable408. In particular embodiments, the flexible inner housing 406 is asmall diameter tubular member (i.e., smaller than the inner diameter ofthe outer tube member) and is secured the key 404 using any of a numberof techniques known to those skilled in the art, which are appropriatefor the materials of use. In an exemplary embodiment, the flexible innerhousing is secured to the key 404 using an adhesive, such as a medicalgrade adhesive.

The barbed fitting 412 is secured to the end of the flexible innerhousing that is opposite to the drill bit 410 using any of a number oftechniques known to those skilled in the art, which are appropriate forthe materials of use. The end of the barbed fitting 412 being secured tothe flexible inner housing 406 also is received within the flexibleinner housing. In particular embodiments, the barbed fitting 412 isconfigured and arranged so the end being received in the flexible innerhousing 406 is secured thereto by an interference fit. In furtherexemplary embodiments, the interference fit is augmented by use of anadhesive, such as a medical grade adhesive.

The proximal drive cable bearing 418 is disposed within the barbedfitting 412 in which is received the drive cable 408. In particularembodiments, the proximal drive cable bearing 418 is retained within thebarbed fitting 412 using any of a number of techniques known to thoseskilled in the art. In an exemplary embodiment, the proximal drive cablebearing is secured to the barbed fitting using one of soldering, brazingor adhesives.

The distal and proximal drive cable bearings 416, 418 are any of anumber of bearing assemblies known to those skilled in the art andappropriate for the intended use. In particular embodiments, the distaland proximal drive cable bearing 416, 418 are miniature ball bearingassemblies as is known to those skilled in the art (e.g., SR133zz MSC35380799, 0.9375″ bore, 0.1875″ OD, 0.0937″ width, double shielded).

In an alternative embodiment, the inner housing is a double curved innertube of a fixed non-flexible construction. The double curved inner tubehas two radii of curvature, the first radius of curvature involves allbut the most distal section of the inner tube and the second radius ofcurvature involves a smaller portion of the inner tube. The secondradius of curvature is set so as to bring the path of the drive cable408 around so as to enter the proximal end of the distal drive cablebearing 416 in the correct direction. In this way, the fixed inner tubecan be configured and arranged so as to swing wide and make a turn toenter essentially parallel to the axis of an end fitting being swaged tothe end of the inner tube. In this way, fatiguing of the drive cable 408can be minimized and misalignment of the drive cable and the inner tubeproximal the end of the inner tube can be minimized.

Although specific embodiments are described herein for the outer tubemember 402 and the inner tube member or flexible inner housing 406 thisshall not be considered as particularly limiting. The present inventioncontemplates adapting the present invention using any of a number oftechniques known to those skilled in the art whereby a cable isgenerally turned through a protected series of rigid or flexiblecannulas or tubes such that a bit operably coupled to one end of thecable can turn at an end of the outer tube or cannula.

The drill bit 410 or burr is any of a number of cutting tools orimplements known to those skilled in the art and appropriate for theintended use, speed and power developed by the drive motor 20 and thematerial to be drilled. In particular illustrative embodiments, thedrill bit 410 or burr is a spade bit such as that shown in FIGS. 6-8,alternatively and with reference to FIG. 9, the drill bit is ahemispherical bit 410 a.

The drive cable 408 is a flexible cable that is more particularlycomprised of a large number of smaller strands of an appropriatematerial, including but not limited to steel, stainless steel, andtitanium, that are compound wound using any of a number of techniquesknown to those skilled in the art so as to yield a flexible cable havingthe desired width, length, flexibility and strength characteristics. Ina particularly illustrative embodiment, the drive cable 408 is a customwound 1.8 mm (0.072 in.) diameter 7×19 left regular lay strand woundcable. In more particular aspects, the drive cable 408 is manufacturedso as to be capable of being rotated or turned at a high rate of speedor revolution while maintaining its flexibility and such that right handturning of the cable should not result in the unwinding or loosening ofconstruction.

In particular embodiments, the length (“Ldc”) of the drive cable 408shall be controlled so as to maintain a relationship with the length ofthe portion of the drive cable (“Ldci”) that is disposed within theouter cannula or outer tube 402 or correspondingly the arc length of theouter tube. In more particular embodiments, the relationship between thelength of the drive cable 408 and the length of the portion of the drivecable within the outer tube 402 satisfies the following relationshipLdc≦4×Ldci; more particularly satisfies the relationship Ldc≦3×Ldci, andmore specifically satisfies the relationship Ldc≦2×Ldci. In morespecific embodiments, the length of the drive cable 408 is set based onthe particular application or material to be drilled. For example, theoverall cable length is shortened or lengthened based on the relativehardness of the material in which the channel or opening is to be formedin the bone or bony structure. In further embodiments, the flexibleinner housing 406 is configured and arranged so as to have a length thatsatisfies the foregoing relationships.

Referring now to FIG. 17 there is shown a side view of a drillingapparatus 1000 according to another aspect of the present invention thatis illustrated being disposed upon adjacent vertebral bodies. Referenceshall be made to FIGS. 1-3 and 6-9 and the discussion related theretofor features and functions not provided in the following discussion.Such a drilling apparatus 1000 includes a platform assembly 1200 and adrill assembly 1300.

The platform assembly 1200 includes a frame member 1202 and a pluralityof path guard members 1204 and a mechanism for securing the frame to thebone or bony structure. As with the drilling apparatus illustrated inFIG. 1, the securing mechanism comprises a plurality of nail members 206that each pass respectively through each of the path guard members 1204so as to be disposed in the bone or bony structure as herein described.In further embodiments, and as hereinafter described, the platformassembly 1200 can further include a second path guard 205, in caseswhere the drilling apparatus 1000 is used to form a groove or recess inan outer surface of the bone or bony structure thereby providing aprotective structure between the moving and rotating drill bit 410 andthe tissues or other structures or features of the mammalian body (e.g.,nerves, blood vessels) that are proximal the bone or bony structureouter surface.

The frame member 1202 and the first guard members 1204 are configuredand arranged so as to form an essentially rigid structure and frame workto which the drill assembly 1300 is removable attached and at least oneand more particularly two through passages 1205. Each of the throughpassages 1205 are configured and arranged so as to allow the outer tubemember 402 of the drill assembly 1300 to pass there through as drill bit410 is being is being rotated or pivoted about the pivot point. Theframe member 1202 is composed of any one of number of materials known tothose skilled in the art that is appropriate for the intended use andthe anticipated structural loads that can be imposed during use. In anexemplary embodiment, the frame member 1202 is made from stainless steelsuch as a stainless steel bar stock.

The first path guard members 1204 are secured to the frame member 1202using any of a number of techniques known to those skilled in the art sothat the through aperture 1205 extends downwardly towards a bottomsurface thereof. As indicated above, the though passage 1205 in each ofthe first path guard members 1204 are arranged so the outer tube member402 and the drill bit 410 or burr of the drill assembly 1300 are passedthere through. In addition, each of the first path guard members 1204are configured and arranged so as to include a plurality of throughpassages, one for each of the nail members. Reference shall be made tothe foregoing discussion for the nail member through passages 220 ofFIG. 1 for further detail and characteristics of these nail memberthrough apertures.

The frame member 1202 also is configured and arranged so as to provide amechanism for guiding the drill assembly 1300 such that the drill bit410 thereof follows a predetermined arc or radius of rotation. Inillustrative embodiments, the frame member 1202 is configured so as toinclude a web portion 1210 that extends width wise along thecircumferential length of the frame member. In further embodiments, theframe member 1202 is configured and arranged so as to form a step regionor a discontinuous radial region 1212 at the ends of the frame memberproximal the first guard members 1204 so as to form in effect a radialstop.

The drill assembly 1300 generally forms a curved structure, moreparticularly a curved tubular structure, that is coupled to the framemember 1202 as herein described and which thus swings around a pivotpoint or pivot axis that is defined by the frame member 1202. In use,the drill bit 410 rotates about its axis while this axis is held tangentto and swept along an arc of constant radius as defined by the pivotpint. This movement results in or yields a toroidal hole in the bone orbony structure.

The drill assembly includes an outer tube member 402, a key 404, aflexible inner housing 406, a drive cable 408, a drill bit 410 or burr,a barbed fitting 412, a drive adapter 414 and moveable mount member1310. In further embodiments, the drill assembly includes a distal drivecable bearing 416 and a proximal drive cable bearing 418. As indicatedabove reference shall be made to FIGS. 1-3 and 6-9 for details andcharacteristics of the drill assembly 1000 not otherwise shown in FIG.17 or described hereinafter.

The moveable mount member 1310 includes a frame member mounting portion1312 and a drill assembly mating portion 1314 that form an integralstructure. The frame member mounting portion 1312 is configured andarranged so as to be slidably mounted upon the frame member 1202, morespecifically the web portion 1210 thereof. Thus, motion of the framemember mounting portion 1312 along the circumference of the frame member1202 causes the drill bit 410 to in effect rotate about a fixed point,the pivot point defined by the arcuate portion of the frame member.

As with the mating portion 324 of the pivot arm 302, the drill assemblymember mating portion 1314 is configured and arranged so as to receivetherein the drill assembly key 404. Reference shall be made to thediscussion herein for the pivot arm mating portion 324 and the drillassembly key 404 for further details and characteristics of the drillassembly mating portion 1314.

In further embodiments, the moveable mount member 1310 is configured andarranged so as to include a finger grip 1316 at or proximal an end ofthe mount member 1310 that is opposite to the end frame member 1302. Thefinger grip 1316 presents a structural element or feature that isconfigured to allow the thumb and/or fingers of the user to grasp thefinger grip so as to thereby control movement of the moveable mountmember 1310, rotation of the drill bit 410 and to also control thedrilling pressure (i.e., pressure being exerted by the drill bit 410 onthe bone or bony structure while drilling the hole or recess therein. Inillustrated embodiments, the finger grip 1316 presents a small tabhaving bilateral concavities that allow the finger tips to grasp it or athrough aperture.

In an alternative embodiment, the frame member 1202 is configured andarranged so as to comprise two sub-members being spaced from each other.The two sub-members further include a slot or other feature in opposingsurfaces of the sub-members, which slot or other feature extends in thecircumferential direction. In this embodiment, the frame mountingportion 1312 of the movable mount member 1310 is configured and arrangedso as to be received in and slide within the slot in each of theopposing surfaces. In this way, the drill bit 410 can be rotated about afixed point defined by the circumferentially arranged slots in the twosub-members. The foregoing is illustrative of a couple of techniques forconfiguring the frame member 1302 and the frame member mount portion1312 so the drill bit 410 can be rotated about a fixed point beingdefined by the structure of the frame member, however, the foregoingshall not be considered limiting as it is within the scope of thepresent invention to adapt the drilling apparatus of the presentinventions so as to provide a mechanism by which the drill bit can berotated about a fixed point and/or such that the drill bit follows afixed path during the drilling process.

Referring now to FIGS. 18A-C there are shown various views of a drillingapparatus 100 a according to yet another aspect of the present inventionthat is generally comprised of a platform assembly 200, a pivot armassembly 300 a and a drill assembly 400 a. Reference shall be made toFIGS. 1-9 and the discussion related thereto for features and functionsin common with the above-described drilling apparatus 100 shown thereonand not more particularly provided in the following discussion or shownin FIGS. 18A-C. Reference also shall be made to FIGS. 1-9 and thediscussion related thereto for details concerning the removablyattachment of the pivot arm 300 a to the platform assembly 200 and theremovable securing of the platform assembly 200 to the bone or bonystructure.

The pivot arm assembly 302 a includes a radial arm or pivot arm 302 a, apivot pin bracket 304 and a pivot pin 306. The pivot pin bracket 304includes side plates 310 and finger pads 312 that are secured to theside plates, where the pivot pin extends between the side plates. Thepivot pin 306 is received within an aperture 320 in the pivot arm 302 asuch that the pivot arm can rotate about a pivot axis 321. The pivot arm302 a is configure and arranged so as to include a mating portion 324 athat is distal from the end 322 of the pivot arm that is mounted uponthe pivot pin. In further embodiments, the pivot arm includes a fingergrip 326 a. Reference shall be made to the foregoing discussion forFIGS. 1-9 for further details of the pivot pin bracket 304, the pivotpin 306, and certain features of the pivot arm 302 a not describedfurther below. Reference also shall be made to the discussion above forthe pivot arm 302 and the finger grip 326 for further details regardingthe construction other characteristics for the pivot arm 302 a andfinger grip 326 features not expressly described below or shown in FIGS.18A-C.

The drill assembly includes a curved or arcuate member 452, a drivecable 456, a drill bit 410 or burr, a drive adapter 414 and a distaldrive cable bearing 416. Reference shall be made to the foregoingdiscussion for FIGS. 1-9 for further details of the drill bit 410, thedrive adapter 414 and the distal drive cable bearing 416 not otherwiseprovided below or shown on FIGS. 18A-C. Reference also shall be made tothe discussion above for the drive cable 408 for further detailsregarding the construction, width and other features not expresslydescribed below.

As indicated herein any one of a number of motors 20 or motor driveassemblies as is known in the art having sufficient power (e.g., torque)and rotational speed are coupled to the drive adapter 414 including butnot limited to the Micro100 (Linvatech/Hall Surgical 5053-009) orBlachmax (Anspach Blackmax-KT-0). The drive adapter 414 is a swage-typeof fitting that is configured and arranged so it can be swaged upon oneend of the drive cable 456. The drive adapter 414 also is configured andarranged so as to provide an input end arrangement that can bemechanically coupled to the output end of a variety of motors or motordrive assemblies or drills including those identified herein.

The pivot arm mating portion 324 a is secured to a portion of the drillassembly curved or arcuate member 452 using any of a number oftechniques known to those skilled in the art that are appropriate forthe use and materials used in the construction of these features. In aspecific embodiment, the arcuate member 452 is removably secured to thepivot arm-mating portion 324 a (e.g., mechanical fasteners, adhesives)and in other embodiment the arcuate member is secured to the pivotarm-mating portion (e.g., adhesives, soldering, brazing) so as to forman integral structure. In further embodiments, at least a segment orportion of the pivot arm-mating portion 324 a is configured and arrangedso as to complement the shape of the portion of the arcuate member 452being received therein. For example and as illustrated in FIGS. 18A-B,the arcuate member 324 also has a curved or arcuate cross-section. Thus,the pivot arm mating portion 324 a is configured so as to receivetherein a curved member having a curved or arcuate cross section. Thisshall not be considered limiting as the arcuate member 452 can beconfigured and arranged so as to have any of a number of externalcross-sectional shapes.

As indicated above, the arcuate member 452 forms a curved structure thatis attached to the pivot arm 302 a as herein described and which thusswings around the pivot point or pivot axis 321. In use, the drill bit410 rotates about its axis while this axis is held tangent to and sweptalong an arc of constant radius as defined by the distance between themating portion 324 a of the pivot arm 302 a and the pivot axis 321. Thismovement results in or yields a toroidal hole.

The arcuate member 452 is curved to a predetermined radius of curvatureso that the centerline thereof is a set distance from the pivot axis 321of the pivot arm 302 a. In further embodiments, the arcuate member 452is a tubular like member having a portion of the tubular structureremoved so the arcuate member 452 includes a dished area or depressedregion 453 in which is received the drive cable 456 as hereinafterdescribed. In an illustrative embodiment, the dished area or depressedregion 453 is generally curved or circular in cross-section as moreclearly illustrated in FIGS. 18 A, C. This, however, shall not belimiting as other geometric shapes are within the scope of the presentinvention that do not unduly impair the rotational capability of thedrive cable 456 when received in the depressed region 453. In furtherembodiments, the dished area or depressed region 453 of the arcuatemember 452 is sized and arranged so as to be capable of removablyreceiving therein the drive cable 456 and, more particularly so externalsurfaces of the drive cable are within an envelope or boundary definedby the depressed region 453 of the arcuate member.

The distal end 451 of the arcuate member 452 provides a structure inwhich the distal distal cable bearing 416 can be secured therein usingany of a number of techniques known to those skilled in the art that isappropriate for the materials comprising these elements or features. Inexemplary embodiments, the distal cable bearing 416 is secured withinthe arcuate member distal end 451 by brazing or soldering. Such astructure also provides a fixed point of attachment for the drive cable456 such that that end of the drive cable and the drill bit 410 moveswith the rotation of the arcuate member about the pivot axis 321. Inmore particular embodiments, the distal drive cable bearing 416 issecured within the arcuate member 452 such that the outer edge of theouter race of the bearing lies in a radial plane from the pivot point,whereby the axis of the drill bit 410 or burr is arranged so as to betangent to the centerline of the arc of the arcuate member.

When drilling of an aperture or hole in the bone or bony structure isdesired, the surgeon or medical personnel applies a force to the fingerportion 326 a so as to cause the arcuate member 452 to rotate about thepivot axis 321 and so as to cause the distal end 451 of the arcuatemember to also rotate about the pivot axis. As the arcuate member distalend 451 rotates through the platform assembly 200, the drive cable 456also is drawn along with the distal end and also is received in thedepressed region 453 of the arcuate member (e.g., as the cable passesbelow the platform assembly 200). In this way, the rotating drive cable456 is caused to lie within the depressed region 453 while the drivecable 456 is disposed within the bone or bony structure as the channelor aperture is being formed in the bone or bony structure as hereinafterdescribed.

The arcuate member 452 according to this aspect of the present inventionminimizes stress on the drive cable and reduces the amount of accessrequired by the surgeon to perform the surgical procedure. Thearrangement, however, also yields an apparatus that advantageouslycreates a mechanism that allows tissue, muscle, blood vessels (e.g.,aorta) and nerves to pass under and around the platform assembly 200 andalso to localize the drilling elements of the drill assembly 400 awithin the structure of the platform assembly. In addition, the pivotarm assembly 300 a in combination with the platform assembly 200provides a mechanism to control the radial movement radius or motion ofthe drilling elements of the drill assembly 400 a from their insertioninto the bone or bony structure as well as the retraction from the boneor bony structure such that the drilling elements traverse a specificradius of curvature during such insertion and retraction. In this way,the drilling apparatus 100 a according to this aspect of the presentinvention also controls the maximum depth within the bone or bonystructure the drilling elements can attain during use. Thus, and incontrast to conventional techniques, devices and instrumentalities, thedrilling apparatus 100 a of the present invention provides a mechanismthat protects tissues, blood vessels and nerves from damage while thedrilling elements of the drill assembly 400 a are being inserted intoand withdrawn from the bone or bony structure as well as assuring thatthe drilling elements will follow a generally fixed path such that thedrilling elements do not come into contact with nor damage the tissues,blood vessels and nerves proximal to and surrounding the bone or bonystructure while the hole or recess is being formed in the bone or bonystructure. Consequently, the drilling apparatus 100 a of the presentinvention minimizes the potential for damage without having to relysolely on the dexterity or skill of the surgeon as is done withconventional techniques and devices.

In general, the drilling path follows a desired path through theadjacent vertebrae or bony segments because the drilling apparatus, inparticular the frame assembly thereof, is maintained in fixed relationwith respect to the adjacent vertebral bodies or bony segments. However,the physical structure of the bony segments or the adjacent vertebralbodies in some cases creates a configuration in which the drillingassembly needs to be adapted to suit the particulars of the physicalstructure (e.g., the surface of the sacrum is at an angle with respectto the surface of the L-5 vertebrae).

Referring now to FIGS. 21A-B there is shown a side view of a drillingapparatus 3000 according to another aspect of the present invention andin FIG. 23C there is shown a perspective view that illustrates the frameassembly 3200 thereof being disposed upon adjacent vertebral bodies 2.Such a drilling apparatus 3000 includes a platform assembly 3200, apivot arm assembly 300 and a drill assembly 400. It should be recognizedthat the frame assembly 3200 is illustrative and that it is contemplatedthat any of the other frame assemblies herein described are adaptable soas to embody the specifics of the platform assembly of this aspect ofthe present invention. Such a drilling apparatus 3000 is particularlyadaptable to accommodate the physical structure and so as to allowchannels to be formed in adjacent bony segments or adjacent vertebralbodies while minimizing the risk of injury or damage to nearby nerves,tissues, muscles and/or blood vessels. Reference shall be made to FIGS.1-9 and 17-18 and the discussion related thereto for features andfunctions in common with the below-described drilling apparatus 3000shown thereon and not more particularly provided in the followingdiscussion or shown in FIGS. 21A-B.

The platform assembly 3200 includes a frame member 202 and a pluralityof path guard members 3204 a,b and a mechanism for securing the frame tothe bone or bony structure. As with the drilling apparatus illustratedin FIG. 1, the securing mechanism comprises a plurality of nail members206 that each pass respectively through each of the first path guardmembers 3204 a,b so as to be disposed in the bone or bony structure asherein described. In further embodiments, and as hereinafter described,the platform assembly 3200 can further include a second path guard 205,in cases where the drilling apparatus 3000 is used to form a groove orrecess in an outer surface of the bone or bony structure therebyproviding a protective structure between the moving and rotating drillbit 410 and the tissues or other structures or features of the mammalianbody (e.g., nerves, blood vessels) that are proximal the bone or bonystructure outer surface.

The frame member 202 and the first guard members 3204 a,b are configuredand arranged so as to form an essentially rigid structure and frame workto which the drill assembly 300 is removable attached and at least oneand more particularly two through passages 3205 a,b. Each of the throughpassages 3205 a,b are configured and arranged so as to allow the outertube member of the drill assembly 300 to pass there through as drill bit410 is being is being rotated or pivoted about the pivot point. Theframe member 202 is composed of any one of number of materials known tothose skilled in the art that is appropriate for the intended use andthe anticipated structural loads that can be imposed during use. In anexemplary embodiment, the frame member 202 is made from stainless steelsuch as a stainless steel bar stock.

The first path guard members 3204 a,b are each configured and arrangedso the frame assembly 3200 is maintained in a desired orientation withrespect to the adjacent bony segments or adjacent vertebral bodies forformation of the channel. In particular embodiments, the bottom surface3241 a,b of each first path guard members is configured and arranged soas to correspond generally to the opposing surface of the adjacent bonysegment or vertebrae. In an illustrative exemplary embodiment, a bottomsurface 3241 a for one first path guard member 3240 a is formed at anangle with respect to a longitudinal axis of the first path guard memberwhen the opposing surface is at an angle with respect to the desiredorientation of the frame assembly (e.g., the angled surface of thesacrum) such as illustrated in FIG. 23C. In further embodiments, thelength of each first path guard member is adjusted so as to compensatefor differences in relative heights between the frame assemblyattachment point of one adjacent bony segment or vertebral body and theframe assembly attachment point of the other adjacent bony segment orvertebral body. In an illustrative exemplary embodiment, one first pathguard member 3240 a is made longer than the other first path guardmember 3240 b so the frame 202 is maintained in a particular orientationwith respect to the target are such as illustrated in FIG. 23C. In thisway, the frame 202 is oriented so that the channel formed by therotation of the drill bit 410 is along the desired path in the adjacentvertebrae.

The foregoing is illustrative of a couple techniques for maintaining theframe assembly 3200 at a desired orientation with respect to theadjacent bony segments or adjacent vertebral bodies. However, this shallnot be construed as limiting as other techniques can be utilized toaddress the described angular and length as well as other differencesthat may arise because of the physical structure (e.g., adjusting forsurfaces being at angles with respect to more that one axis).

The first path guard members 3204 a,b are secured to the frame member202 using any of a number of techniques known to those skilled in theart so that the through apertures 3205 a,b in the first path guardmembers 3204 a,b extend generally downwardly towards a bottom surface3241 a,b thereof. In further embodiments, particularly when a first pathguard member 3240 b has a different length than the other first pathguard member 3240 a as well as having a bottom surface 3241 a that is atangle with respect to a longitudinal axis of the guard member, thethrough aperture 3205 b may comprise an opening through a side of such afirst path guard member 3204 b or such an opening that extends throughthe side and into the bottom surface. These openings are generallyestablished based on the geometry between the frame assembly 3200 whenit is secured to the adjacent bony segments or adjacent vertebral bodiesand the pivot point for forming the desired channel.

As indicated above, the though passage 3205 a,b in each of the firstpath guard members 1204 are arranged so the outer tube member 402 andthe drill bit 410 or burr of the drill assembly 300 are passed therethrough. In addition, each of the first path guard members 3204 a,b areconfigured and arranged so as to include a plurality of throughpassages, one for each of the nail members. Reference shall be made tothe foregoing discussion for the nail member through passages 220 ofFIG. 1 for further detail and characteristics of these nail memberthrough apertures.

The arrangement of the drilling apparatus 3000 yields an apparatus thatadvantageously creates a mechanism that allows tissue, muscle, bloodvessels (e.g., aorta) and nerves to pass under and around the platformassembly 3200, to localize the drilling elements of the drill assembly400 within the structure of the platform assembly and to provide amechanism to compensate for any differences between the adjacent bonystructure or adjacent vertebrae. In addition, the pivot arm assembly 300in combination with the platform assembly 3200 provides a mechanism tocontrol the radial movement radius or motion of the drilling elements ofthe drill assembly 400 from their insertion into the bone or bonystructure as well as the retraction from the bone or bony structure suchthat the drilling elements traverse a specific radius of curvatureduring such insertion and retraction. In this way, the drillingapparatus 3200 according to this aspect of the present invention alsocontrols the maximum depth within the bone or bony structure thedrilling elements can attain during use. Thus, and in contrast toconventional techniques, devices and instrumentalities, the drillingapparatus 3200 of the present invention provides a mechanism thatprotects tissues, blood vessels and nerves from damage while thedrilling elements of the drill assembly 400 are being inserted into andwithdrawn from the bone or bony structure as well as assuring that thedrilling elements will follow a generally fixed path such that thedrilling elements do not come into contact with nor damage the tissues,blood vessels and nerves proximal to and surrounding the bone or bonystructure while the hole or recess is being formed in the bone or bonystructure. Consequently, the drilling apparatus 3200 of the presentinvention minimizes the potential for damage without having to relysolely on the dexterity or skill of the surgeon as is done withconventional techniques and devices.

Upon completion of the procedure involving use of the drill assembly 100of the present invention, and as described herein, the nail members 206are acted upon so as to remove each of the nail members from the bone orbony structure or spine. This removal can be accomplished using any of anumber of techniques or devices known those skilled in the art. Inparticular embodiments of the present invention, and with reference toFIGS. 10A,B, there is shown a side view and an end view respectively ofa nail member removal device 500 according to the present invention.Reference also should be made to FIG. 11, which illustrates the removaltechnique using such a nail member removal device 500.

The nail member removal device 500 includes a block member 502 and aknurled screw member 506. The block member 502 includes a throughpassage that extends lengthwise in the block member so as to form asaddle structure that can straddle and slide along side rails 203 of theframe 202. In further embodiments, the block member 502 includes aslotted passage 512 that extends from a bottom surface to a top surfaceof the block member and extends partially lengthwise to a surface of thethrough aperture 504 or hole that is formed in the block member. Theslotted passage 512 also is generally sized so to allow the block memberto slide past the head portion 230 that is sticking up above the topsurface 210 a of the frame, more particularly the side rails thereof.

The threaded aperture 504 or hole is positioned within the block member502 so that it can be centered over one of the head portions 230 of thenail members 206. In use, the nail members 206 are typically driven intothe bone or bony structure such that a bottom surface of the headportion 230 is proud of or above the frame top surface 210 a. As such alower portion of the knurled screw member 506 is machined so as toinclude a side pocket 514 therein. The side pocket 514 is made in thescrew member 506 so as to have sufficient depth (e.g., width) and lengthto accommodate the head portion coaxially therein. The bottom segment ofthe screw member 506 also includes a notch that extends generallyradially to allow the nail member shaft portion 232 to be receivedtherein and so as to be also coaxial with the screw member.

In particular embodiments, when the screw member 506 is rotated in onedirection (e.g., clockwise) the side pocket 514 can be aligned with theslotted through passage 512 and thus be ready to receive therein a nailmember head portion 230. The block member 502 is slide along the frameside rail 203 until the head portion is contained within the side pocket514. After the head portion is disposed in the side pocket, the screw isrotated in the opposite direction (e.g., counterclockwise) therebycausing the screw to rotate in an upwardly direction drawing the notchedbottom surface of the side pocket into contact with the bottom surfaceof the head portion. When the notched bottom surface of the side pocket514 engages the bottom surface of the head portion, continued rotationof the screw member 506 also causes the head portion to be movedupwardly. In this way, the pointed end of the shaft portion is withdrawnfrom the bone or bony structure.

In more particular embodiments, the block member 502 and the slottedpassage 512 therein are formed such that a portion of the block memberis disposed over an end portion of the end rail of the frame 203. Thisestablishes a configuration whereby the pulling load is applied betweentwo support points, thereby minimizing the potential for tipping of thenail member removal device 500 due to unbalanced force couples.

As indicated herein, prior to use of the drilling capabilities of thedrilling assembly 100 of the present invention, the nail members aredriven into contact with the constricted regions of the first pathguards 204 and into engagement with the bone or bony structure or spine.This driving of the nail members can be accomplished using any of anumber of techniques or devices known those skilled in the art. Inparticular embodiments of the present invention, and with reference toFIG. 12 there is shown a side view with a partial cut-away of a nailmember drive tool 600 according to the present invention.

The drive tool 600 is a generally cylindrical member having a blind hole602 or aperture in one end thereof. The blind hole 602 is sized so as toreceive therein a head portion 230 of a nail member 206. The drive tool600 is constructed so that an impact load, such as that imparted by ahammer, at the opposite end 604 thereof drives the nail member 206disposed in the blind hole 602. In further embodiments, the blind hole602 also is sized so as to generally prevent the tool from slipping offthe head portion. In yet further embodiments, the depth of the blindhole 602 is set so that the bottom surface of the head portion 230remains a predetermined distance above the frame top surface 210 a so asto allow the head portion to be later received in the side pocket of thescrew member 506 of the nail member removal device 500.

As indicated herein the drilling apparatus 100 of the present inventionis adaptable for use for forming recesses or holes in bones, bonystructures or the spine of a mammalian body. The following describes theuse of the drilling apparatus in connection with two differenttechniques (i.e., anterior approach and medial approach) for forming arecess or an aperture in adjacent vertebral bodies of a spine. Althoughthe following discussion specifically refers to the drilling apparatus100 shown in FIG. 1 it shall be understood that the below describedtechniques can be used in conjunction with the drilling apparatus 1000,100 a shown in FIGS. 17-18 as well as other embodiments of suchapparatuses 100, 100 a, 1000. Referring now to FIGS. 13A-L there isshown a series of views illustrating the process for the anteriorapproach. Reference shall also be made to FIGS. 1-11 and 17-18 and thediscussion related thereto for features and functions not provided inthe following discussion.

The area of concern is exposed by a surgeon using one of atransperitoneal or retroperitoneal approach, as shown in FIG. 13A and adiscetomy is performed at the level to be instrumented and immobilized.After placing a support (e.g., a femoral ring allograft) in the discspace, lateral stabilization is performed (see FIG. 13B).

The drilling apparatus frame 202 is aligned such that it is vertical inan anteroposterior orientation and placed as far lateral as possible onthe anterolateral aspect of the vertebrae across the operative level.Temporary placement pins 700 are driven into the vertebral cortex tohold the frame 202 in place while creating the channel or recess. Inaddition, the present invention contemplates the addition of a secondpath guard 204 b that extends between the first path guards 204. Thesecond path guard 204 b is arcuate or curved having a radius thatgenerally corresponds to the path of the drill bit 410. The second pathguide 204 b also is configured so as to extend outwardly from thevertebral cortex so as to provide a barrier between the drill bit travelpath and tissues, nerves and blood vessels proximal the site. The secondpath guard 204 b is constructed of similar materials as the first pathguards 204. See FIGS. 13D-E.

When the frame 202 is positioned in the intended fashion, the pivot armassembly 300 is located and secured within the frame 202, thereby alsosecuring the drill assembly 200 in the frame. See FIG. 13E. The drivemotor 20 or drive motor assembly is then secured to the adapter 414. Thepivot arm 302 is then positioned so the drill assembly/drill bit is inthe starting position so the channel or recess can be cut. See FIG. 13F.

The drill motor 20 is started so as to cause the drill bit 410 to rotateat the desired speed and power, and the pivot arm 302 is rotated aboutthe pivot point thereby causing the drill bit 410 to rotate in apredetermined direction in a downward, circular path as dictated by theframe and the pivot arm. The resulting cut should be made immediatelyadjacent to the lateral vertebral surface. This cut is complete when thedrill bit 410 reaches the disc space as shown in FIG. 13G.

Once the first half of the channel is cut, and with the drive motor 20turned off and/or disconnected from the adapter 414, the pivot arm isrotated in the opposite direction to return it to the starting position,where the pivot arm assembly 300 can be removed from the frame 202.After removing the pivot arm assembly 300 from the frame 202, the pivotarm assembly is flipped to the opposites side of the frame andreconnected to the frame. In this way, a matching channel can be cutinto the other vertebra adjacent to the operative level. See FIG. 13H.As with the first cut, the drive motor 20 is turned on and the pivot armrotated so the drill bit 410 follows a downward, circular path. Afterthe second half of the channel has been cut, the pivot arm is returnedto the starting position and the pivot arm assembly 300 is removed fromthe frame 202. See FIGS. 13I-J.

The temporary placement pins 700 are removed from the vertebral bodiesand the frame 202 is removed from the operative site (see FIG. 13K) anda standard osteotome chisel can be used to remove any remaining bonefrom the channel edges so that the channel is open to receive or acceptthe curved rod.

Now with reference with FIGS. 14A-D there is shown the process forplacing, positioning and attaching or implanting a curved rod 800,including those described in any of U.S. Pat. No. 6,607,530 and U.S.Ser. No. 10/019,265, the teachings of which are incorporated herein byreference. The curved rod 800 is positioned in the channel and securedto the vertebral bodies using interlocking screws 802, 804 that traversethe rod and penetrate the vertebra at an angle that will avoid sensitiveneurologic structures. The screws hold the curved rod 800 in place andstabilize the motion segment to facilitate healing of the bone withinthe disc space.

Two lateral screws 802 pass through the lateral holes of the curved rodand set on the lateral surface of the implant. The two end screws 804are passed through the open ends of the curved rod and each is inserteduntil the screw head is contained within the hollow of the implant. Thelateral and end screws are inserted using for example a Cardanscrewdriver 806. As shown in FIGS. 14C-D the curved rod is now securelyin place in either of the recess (FIG. 14C) or a surface-mountedconfiguration (FIG. 14D).

Referring now to FIGS. 15A-H there is shown a series of viewsillustrating the process for the medial approach. Reference shall alsobe made to FIGS. 1-11 and 17-18 and the discussion related thereto aswell as for FIGS. 13-14 for features and functions not provided in thefollowing discussion. As above, the area of concern is exposed by asurgeon using the appropriate technique and the drilling apparatus frame202 is aligned such that it is vertical in an anteroposteriororientation and placed as far midline as possible on the anterior aspectof the vertebrae across the operative level. The pointed ends of thenail members 206 are then driven through the platform frame 202 and thefirst path guards 204 so as to be driven into the vertegral cortex tohold the frame in place while cutting the channel or through aperture.See FIG. 15A-B.

The pivot arm assembly 300 is then secured to the frame 202 and therebyalso securing the drill assembly to the frame. The drive motor 20 alsois coupled to the drill assembly 300 via the adapter 414 See FIG. 15C.The pivot arm 302 is then rotated until the drill bit 410 and the pivotarm are in the start position, whereat the drill motor 20 is started.See FIG. 15D. The pivot arm is rotated so as to cause the drill bit totravel in a downward circular path thereby making cuts in the vertebralbody. In the case where, the first cut does not cut a complete channelor through aperture, the pivot arm assembly is detached from the frame,flipped, reconnected to the frame and the cutting process describedabove is repeated until the rest of the channel or through aperture hasbeen cut. See FIGS. 15D-F.

There is shown in FIG. 15I, a illustrative view of adjacent vertebralbodies with the drilling apparatus 100 of the present invention mountedthereon. As illustrated, the arrangement of the drilling apparatus 100of the present invention is such that the drilling bit follows a fixedpath established by the configuration of the drilling apparatus 100. Inthis way, a maximum or fixed cutting depth also is set or established bythe configuration of the drilling apparatus 100.

After the complete channel or through aperture is cut in the adjacentvertebral bodies, the pivot arm assembly 300 and the drill assembly 400are detached from the frame 202 and the nail members 206 are removedfrom the vertebral bodies and the frame or platform assembly 200 isremoved from the operative site. As indicated herein, removal of thenail members 206 can be accomplished using the nail member removaldevice 500 of the present invention. The above process yields a channelopening or through aperture in both vertebral bodies that can accept thecurved rod 800. See FIGS. 15G-H.

It should be recognized that it is within the scope of the presentinvention to cut a channel through or partially through one of thevertebral bodies. Thus, the foregoing process is adaptable foraccomplishing this by limiting rotational movement such that a channelis not cut completely through one of the vertebral bodies.

Now with reference to FIGS. 16A-C there is shown the process forplacing, positioning and attaching or implanting a curved rod 800,including those described in any of U.S. Pat. No. 6,607,530 and U.S.Ser. No. 10/019,265, the teachings of which are incorporated herein byreference. The curved rod 800 is inserted into the channel andmanipulated so that the curved rod is submerged along the midline of thevertebra (see FIGS. 16A-B). The curved rod 800 is now secured to thevertebral bodies using interlocking screws 804 that traverse the rod andpenetrate the vertebra at an angle that will avoid sensitive neurologicstructures. The screws hold the curved rod 800 in place and stabilizethe motion segment to facilitate healing of the bone within the discspace.

Two end screws 804 are passed through the open ends of the curved rodand each is inserted until the screw head is contained within the hollowof the implant. The screws are inserted using for example a Cardanscrewdriver 806.

It should be recognized, and as taught in any of U.S. Pat. No. 6,607,530and U.S. Ser. No. 10/019,265, the teachings of which are incorporatedherein by reference, the curved rods 800 can be configured so as toinclude fenestration or surface artifacts that secure the curved rodwithin the channel without the retaining screws 804 are described aboveor in addition to such retaining screws.

In addition to the foregoing teachings of any of U.S. Pat. No. 6,607,530and U.S. Ser. No. 10/019,265 as to the type and form of rod or implantthat can be placed, positioned, attached and/or implanted, there areshown in FIGS. 22-24 other implants that are contemplated for use withthe methodology, devices and/or apparatuses of the present invention aswell as for use in combination with any of a number of othermethodologies, devices and/or apparatuses described in U.S. Pat. No.6,607,530 and U.S. Ser. No. 10/019,265. Now with reference to FIGS.23A,B there is shown a sliding implant device 850 or a dynamized implantdevice that includes first and second members that are configured andarranged so as to form a sliding interconnection 854 there between. Sucha sliding implant device 850 provides a mechanism to provide stabilityto the spine while preserving at least some ability of motion in thespine. Such a device provides dynamic stabilization to a patient whoneeds stability but necessarily fusion of adjacent vertebrae.

In a particular embodiment, the sliding interconnection 854 is formed byhaving an end 851 a of the first member 852 a being slidably disposedwith an end 851 b of the second member 852 b. As illustrated in FIG.22B, in the inner diameter of at least the end 851 a of the first member852 a is larger than the outer diameter of the end of the second end 851b of the second member 852 b. This can be achieved using any of a numberof techniques known to those skilled in the art. As illustration, in onecase the first member end 851 a is machined or processed so that thisend is expanded radially outwardly so as to form a socket for receivingthe send member end 851 b. In another case, the second member 852 b isformed so the end 851 b has an outer diameter that is set so as toslidably received within the first member end 851 a. In yet anothercase, the first member 852 a is formed so that the end 851 a includes apocket therein and the second member 852 b is formed so the end 851 bhas an outer diameter that is set so as to slidably received within thepocket of the first member end 851 a.

In further embodiments, the first member 852 a is a solid member and theend 851 a is formed so as to create a pocket or socket within the firstmember and the second member 852 b is a solid member and the end 851 athereof is formed so as to have a reduced diameter so as to form a plugtype end that can be slidably received within the socket/pocket of thefirst member 852 a. In this way, the shoulder of the plug end and thelip of the first member end cooperate to stop further relative motionbetween the first and second members 852 a,b. In further embodiments,the first and second members 852 a,b have respective different outerdiameters such that the outer diameter of the second member 852 b isless than the inner diameter of the first member or the pocket/socket onthe end 851 a thereof.

In further particular embodiments, and with reference to FIG. 22B, therespective ends 851 a,b of the first and second members 852 a,b also arearranged so as to include stop members 856 a,b that cooperate torestrict relative movement between the first and second members as wellas restrict relative movement between the adjacent vertebrae 2. Inexemplary embodiment, the stop members 856 a,b extend outwardly fromopposing surfaces of the first and second members 852 a,b. The stopmembers 856 a,b also are arranged such that when the first and secondmembers are secured within the adjacent vertebrae 2, the stop membersare opposed to each other and spaced from each other corresponding to agiven spacing between the adjacent vertebrae.

Thus, when the spacing between the adjacent vertebrae changes responsiveto relative movement of the adjacent vertebrae (e.g., compression), suchrelative movement also causes the stop members 856 a,b to also move withrespect to each other. When the stop members 856 a,b contact each other,however, further relative movement between the first and second members852 a,b as well as between the adjacent vertebrae is restrained. Thus,the spacing between the stop members in effects sets the dynamic rangeof movement for the adjacent vertebrae. In further embodiments, thespacing between the stop members 856 a,b is adjusted so as to providedifferent dynamic ranges of movement.

In further exemplary embodiments, each of the stop members 856 a,bcomprise a plurality or more of segments, each segment extending aroundpart of the circumference of the respective first and second members soas to form channels between the adjacent segments of a respective firstor second member. These channels form paths through which the stopmember segments of the other of the first and second member can passaxially when forming the sliding interconnection. When the first andsecond members 852 a,b are assembled to form the slidinginterconnection, the stop member segments are rotated with respect toeach other so that they are orientated opposed to each other.

In further exemplary embodiments, the stop members 856 a,b and the stopmember segments, are formed integral with the respective first andsecond members 852 a,b. In alternative embodiments, the stop members 856a,b and the stop member segments, are coupled or secured to therespective first and second members 852 a,b using any of a number oftechniques known to those skilled in the art (e.g., adhesives, welding,brazing, ultrasonic welding, laser welding, or other mechanicalconnections) and appropriate for the structure forming the first andsecond members 852 a,b of the implant device.

Referring now to FIGS. 23A-C there is shown another embodiment of adynamized implant device 860 that includes first and second members 862a,b members, that are configured and arranged so as to form a sliding orpiston-like interconnection between opposing ends of the respectivefirst and second members, and a compressive device 864 that is disposedbetween opposing ends of the respective first and second members. Such adynamized implant device 860 provides a mechanism to provide stabilityto the spine while preserving at least some ability of motion in thespine. Such a device provides dynamic stabilization to a patient whoneeds stability but necessarily fusion of adjacent vertebrae.

The compressive device 864 comprises a spring, a compressive material,for example a bio-compatible foam material or other resilient orcompressive material as is known to those skilled in art. In exemplaryembodiments, the compressive device is operably coupled or secured toone of the opposing ends and in more particular embodiments is operablycoupled to both opposing ends. For example, when a spring comprises thecompressive device 864 one end of the spring is secured to the end 861 aof the first member 862 a and the other end of the spring is secured tothe end 861 b of the first member 862 a.

In a further exemplary embodiment, and with reference to FIG. 23B, theends 861 a′,b′ of the respective first and second members 862 a′,b′ arearranged so the first member end 861 a′ is slidably disposed within apocket 866 in the end 861 b′ of the second member b′. Also, thecompressive device 864 is disposed within the pocket and between theends 861 a′,b′ of the first and second members.

In another further exemplary embodiment, and with reference to FIG. 23C,the end 861 a″ of the first member 862 a″ is configured so itscross-section or outer diameter is reduced with respect to that of therest of the first member so as to from a plug 863 a or piston-likemember. In this arrangement, the plug like member 863, is slidablydisposed within a pocket 866 in the end 861 b of the second member 862b″. Also, the compressive device 864 is disposed within the pocket andbetween the ends 861 a″,b″ of the respective first and second members.

Although the foregoing discussion, has generally described the presentinvention in terms of implanting one arcuate rod or implant devicebetween bony segments such as between adjacent vertebrae, this shall notbe construed as a limitation as it is contemplated and thus within thescope of the present invention for a plurality or more of implantdevices 900 (FIGS. 24A,B) to be positioned and secured between adjacentbony segments including adjacent vertebrae. In further embodiments, theplurality or more of implant devices 900 can both have the same generalmakeup or constitution or the plurality or more of implant devices 900can be different. Thus, and in addition to the foregoing teachings ofany of U.S. Pat. No. 6,607,530 and U.S. Ser. No. 10/019,265 as well asthat described hereinabove, the methods of the present invention canfurther include placing, positioning and attaching or implanting aplurality of implants 900.

In addition to securing a plurality of implant devices in adjacentvertebrae is also is contemplated and thus within the scope of thepresent invention to position and secure one or more arcuate rods orimplant devices in three or more adjacent vertebrae. Referring now toFIG. 24C, there is shown an illustrative embodiment in which two or morearcuate rods or implant devices 900 a 1,a2 are stacked or overlaid sothat there is an implant device 900 a 1 extending between adjacentvertebrae 2 a,b and another implant device 900 a 2 extending betweenadjacent vertebrae 2 b,2 c. In this illustrative embodiment, an end 901a 1,901 a 2 of each implant device 900 a 1,900 a 2 is located andsecured in the same vertebrae 2 b by a screw 910 or other type of deviceknown to those skilled in the art. The other end 903 a 1, 903 a 2 issecured in the respective vertebrae 2 a,2 c by a screw 910. Inparticular embodiments, and with reference to the anterior view shown inFIG. 24D, the ends 901 a 1, 901 a 2 being secured in the middlevertebrae 2 b are configured and arrange so that one end 901 a 2 isconfigured so as to be disposed about the other end 901 a 1.

Referring now to FIG. 24E there is shown another illustrativeembodiment, in which the one arcuate rod or implant device 900 b 1 isconfigured so as to be shorter than the other implant device 900 b 2. Aswith the embodiment described above, one end 903 b 1, 903 b 2 of eachimplant device 900 b 1,b2 is secured in the respective vertebrae 2 a,2 cby a screw 910. The shorter implant device 900 b 1 is configured so anend 901 b 1 thereof is disposed about a portion of the longer implantdevice 900 b 2 that is proximal to the end 901 b 2 that is to be securedin the middle vertebrae 2 b by the screw 910. The end 901 b 1 of theshorter implant device also is configured so that the screw 910 exitingfrom the longer implant device 900 b 2 also passes through the end 901 b1 so as to secure both ends 901 b 1,b2 in the middle vertebrae 2 b.

As indicated herein, the drilling apparatus of the present invention isadaptable for use in a wide range of spinal repair procedures includingbut not limited to a repair procedure for an intervertebral disk 5 (FIG.19A,B). Although the following discussion refers to the drillingapparatus 100 according to one aspect/embodiment of the presentinvention, it is contemplated that any of the drilling apparatusesherein described are adaptable for use to perform such a disk repairprocedure. Also, it is contemplated that a disk repair procedureaccording to the present invention also can be accomplished using any ofthe devices, apparatuses or mechanisms described in and as taught in anyof U.S. Pat. No. 6,607,530 and U.S. Ser. No. 10/019,265.

Referring now to FIGS. 19A-B, there is shown a drilling apparatus 100mounted/secured upon a spine, more specifically adjacent vertebrae 2,Step 2000. Such mounting and securing is accomplished using the methodsand techniques for doing so as described herein. Reference shall be madeto FIGS. 1-9 and the discussion related thereto, for further details ofthe drilling apparatus not provided below. Reference also should be madeto the process flow diagram illustrated in FIG. 20.

In further embodiments, the drill bit 410 of the drilling apparatus 100and related components are selected so that the channel, passage or hole3 in the adjacent vertebrae 2 is sized so as to provide a desired accessto the nucleus for carrying out the repair procedure. For example, thehole 3 may be one size if a fluid or gel is to be injected into thenucleus, whereas it may be made larger if a prosthetic or device is tobe inserted through the hole so as to reside in the area within theannulus for the disk nucleus.

After the drilling apparatus 100 is so mounted, the surgeon wouldmanipulate the drill bit so as to cause it to rotate and create a curvedor arcuate hole 3 in the adjacent vertebrae and into the disk 5, Step2002. Such a drilling operation advantageously minimizes penetration ofthe vertebral endplates. Also, the drill as it follows the predeterminedcurved or arcuate path penetrates the vertebral end plates atessentially a right angle, thereby creating a circular defect. Incontrast, the straight drill used in conventional techniques wouldpenetrate the end plate at an angle thereby causing a larger ellipticalshaped defect. The near perpendicular access created by the drillingapparatus of the present invention also minimizes trauma and/ordisruption to the natural nucleus material. In contrast, a straightdrill would need to penetrate more deeply into the disc space tocomplete the access hole.

In this regard it should be noted that while it is desirous to penetratethe nucleus of the disk, it should be recognized that it is possiblethat a portion of the annulus also may be drilled during the drillingprocedure. Such an occurrence, however, shall not be construed as beingunacceptable or outside the scope of the present invention.

Following creating of the hole, the drill bit 410 is extracted orremoved from the hole 3 thereby allowing the surgeon access to the holeand thus the nucleus of the disk to be repaired. In particularembodiments, the surgeon would remove the drilling apparatus 100 so asto provide clear access to the opening formed by the hole 3, Step 2004.Thereafter, the surgeon would perform the particulars of the diskrepair/replacing/augmentation procedure, such as but not limited toremoving nucleus material (Step 2006), delivery of the nucleusaugmentation material, artificial disk and/or artificial nucleus (Step2008) and plugging of the channel, passage or hole 3 made in theadjacent vertebrae 2 (Step 2010). The nucleus material can be removedusing any of a number of techniques known to those skilled in the artincluding but not limited to water jets, chemical agents such asChymopapain chemonucleolysis, rongers and emulsification technology.

Such augmentation material includes but is not limited to the devices,mechanisms and materials described in U.S. Pat. No. 5,824,093, U.S. Pat.No. 6,264,695 and U.S. Pat. No. 5,047,055 the teachings of which areherein incorporated by reference. Also, such delivery of the nucleusaugmentation material, as well as such repair procedures, can includedelivery and positioning of an annulus closure mechanism or device toseal or retain the artificial disc, nucleus and/or nucleus augmentationmaterial or provide a closure for a defect in the annulus (such as butno limited to the devices described in U.S. Pat. Nos. 6,425,919 and6,593,625, the teaching of which are incorporated herein by reference).As is known to those skilled in the art, when the annulus becomesdamaged a defect is formed in the annulus that allows the nucleus forexample, to cause the disk to bulge in a given direction. In addition,to delivery of nucleus or annulus repair and augmentation materials, italso is contemplated that drugs, medicaments, or other treatmentmaterials can be delivered to the disk 5, vertebrae 2 or other elementof the body.

The plugging of the hole 3 is accomplished using any of a number oftechniques known to those skilled in the art, including but not limitedto the use of bone/bone graft material. It also is contemplated that anarcuate rod as herein described also can be used to plug the hole 3.Thus, the plugging of the hole 3 becomes a relatively straightforwardprocedure. Also, the plugging should advantageously create a relativelysmooth surface at the end plate and the load forces on the vertebral endplate will be perpendicular to the access hole. Such plugging isparticularly advantageous as compared to some conventional techniques asdefects in the annulus do not heal; whereas defects in the bone (e.g.,the vertebral body) can be plugged with bone, metal, etc. and the boneheals around the plug.

Referring now to FIGS. 25-29 there is shown exemplary frame assembliesfor a drilling assembly according to another aspect of the presentinvention, in which an intervertebral spacer or spacer element isremovably secured to and extends from the frame assembly so as to bemaintained in a fixed relation to the frame assembly as the channel isbeing formed in the adjacent bony segments or adjacent vertebral bodies.In particular embodiments, the intervertebral spacer is secured to theframe assembly so as to prevent rotational motion of the intervertebralspacer with respect to the channel. Such an arrangement provides amechanism thereby also provides a mechanism for maintaining alignment ofthe spacer to the channel as well as to the position of the drill. Theintervertebral spacer also allows the surgeon to maintain extremelyaccurate disk spacing and also protects the spinal cord.

In further embodiments, the intervertebral spacer is formed so that thedrill bit 410 as it is being rotated to form the channel passes throughthe spacer thereby also forming an aperture in the spacer that hascorresponds characteristics as the channel formed in the adjacent bonystructure/vertebral bodies (e.g., same curvature, diameter). In anotherembodiment, the intervertebral spacer is formed so as to include apre-formed aperture; through which the drill bit 410 passes as the drillbit is being rotated to form the channel in the adjacent bony structureor adjacent vertebral bodies. In yet another embodiment, theintervertebral spacer is formed so as to include a pre-formed aperturesmaller than the channel to be formed. The drill bit 410 passes throughthe portion of the spacer including the pre-formed aperture as the drillbit is being rotated, thereby forming the channel in the adjacent bonystructure or adjacent vertebral bodies. Such intervertebral spacers canbe made using any of a number of techniques and materials known to thoseskilled in the art and in particular embodiments, the spacer design issuitably based on a construction that facilitates the selected techniquefor creating an arcuate aperture. In more particular embodiments, theintervertebral spacers are bone, metal, allograft, autologous, plastic(e.g., PEK) or other material appropriate for the intended use.

In further embodiments, the surgical personnel select an intervertebralspacer that is appropriately sized, so it can accommodate the distendeddisc space. In yet further embodiments, the mechanism securing theintervertebral spacer to the frame assembly is disengaged therebyreleasing the spacer from the drilling apparatus following the drillingor forming of the channel in the adjacent bony segments or vertebralbodies. In this way, the intervertebral spacer remains disposed in theintertertebral disc space. In yet further embodiments, the implant orarcuate rod is inserted into and through the through aperture in thespacer so as to thereby secure the spacer between the intervetebralbodies.

Referring now to FIGS. 25A-C there is shown one embodiment of anexemplary frame assembly 4200 according to this aspect of the presentinvention, in which the frame 4202 includes a plurality of sideprotrusions 4290 that are positioned at about the mid-point of the frameand on either side of the frame. Each of the side protrusions includes athrough aperture 4291. The exemplary frame assembly 4200 also included aplurality of posts 4292 or connectors; each of which are disposed in oneof the protrusion through apertures 4291. The posts 4292 are generallyarranged so that an end 4293 a thereof is generally directed towards theintervertebral space between the vertebral bodies 2.

In particular embodiments, this end 4293 a of the posts 4292 isconfigured so the post or connector is releasably secured to theintervertebral spacer 4800. In illustrative exemplary embodiments, anaperture 4804 provided in the spacer 4800 and the end 4293 a of theposts 4292 are threaded, whereby the spacer is threadably secured to theposts. In further embodiments, the other end 4293 b of the posts 4292 isconfigured so has to have a head or other feature that prevents the postfrom passing through the protrusion through aperture 4291. In yetfurther embodiments, the length of each post is established such thatwhen the intervertebral spacer 4800 is so secured to the frame assemblythe spacer is appropriately positioned with respect to the travel pathof the drill bit 410 as it is being rotated to form the channel. Inparticular embodiments, the intervertebral spacer 4800 is secured to theframe assembly so the pre-formed aperture 4802 in the spacer isappropriately positioned and so as to be congruent with the travel pathof the drill bit 410 as it is being rotated to form the channel.

Referring now to FIGS. 26A-B there is shown another embodiment of anexemplary frame assembly 4200 a according to this aspect of the presentinvention, in which the frame 4202 a includes a plurality of sideprotrusions 4290 a that are positioned away from the mid-point of theframe and on either side of the frame. Each of the side protrusionsincludes a through aperture 4291. The exemplary frame assembly 4200 aalso included a plurality of posts 4292 a or connectors; each of whichare disposed in one of the protrusion through apertures 4291. The posts4292 are generally arranged so that they extend at an angle from eachprotrusion and so that an end 4293 aa thereof is generally directedtowards the intervertebral space between the vertebral bodies 2.

In particular embodiments, this end 4293 aa of the posts 4292 a isconfigured so the post or connector is releasably secured to theintervertebral spacer 4800. In illustrative exemplary embodiments, anaperture 4804 provided in the spacer 4800 and the end 4293 aa of theposts 4292 a are threaded, whereby the spacer is threadably secured tothe posts. In further embodiments, the other end 4293 ab of the posts4292 is configured so has to have a head or other feature that preventsthe post from passing through the protrusion through aperture 4291. Theother end 4293 ab also is configured so the surface contacting the frame4202 a complements the angle of the posts. In yet further embodiments,the length of each post 4292 aa is established such that when theintervertebral spacer 4800 is so secured to the frame assembly thespacer is appropriately positioned with respect to the travel path ofthe drill bit 410 as it is being rotated to form the channel. Inparticular embodiments, the intervertebral spacer 4800 is secured to theframe assembly so the pre-formed aperture 4802 in the spacer isappropriately positioned and so as to be congruent with the travel pathof the drill bit 410 as it is being rotated to form the channel.

Referring now to FIGS. 27A-C there is shown another embodiment of anexemplary frame assembly 5200 a according to this aspect of the presentinvention that includes a frame 5202 and a clip mechanism 5210. The clipmechanism 5210 is attached or secured to the frame 5202 using any of anumber of techniques known to those skilled in the art so thatmanipulation of the clip mechanism by a clinician or other medicalpersonnel does not result in the detachment of the clip mechanism. In anillustrative exemplary embodiment, the clip mechanism 5210 includes arecessed portion 5218 in which is received portions of the frame 5202.In more particular embodiments, the clip mechanism 5210 is attached onthe interior of the frame 5202 so that the clip portion 5212 thereofextends downwardly through the frame.

The clip mechanism 5210 is made of any of a number of bio-compatiblematerials, such as stainless steel and/or plastic, that are appropriatefor the intended use (e.g., compatible with the material of the frame)and which can be attached or secured to the frame 5202.

The clip portion 5212 of the clip mechanism 5210 is configured so as toreleasably hold the intervertebral spacer 4800 in the interior space5214 of the clip portion. In use the surgeon manipulates the lever arms5216 thereby causing the clip portion 5212 to release the intervertebralspacer. In particular embodiments, the manipulation of the lever arms5216 causes the opposing arm segments of the clip portion 5212 to moveaway from each other so the spacer can pass out of the interior space5214.

In further embodiments, the clip portion 5212 is configured so as toinclude a plurality of pairs of arm segments that are spaced from eachother along the length of the frame 5202, where each pair of armsegments releasably holds the intervertebral spacer 4800. For exampleand as illustrated in FIG. 27B, one pair of arm segments can be locatedforward of the midpoint of the frame and the other pair of arm segmentscan be located rearward of the frame midpoint. In addition, there alsois provided a plurality of pairs of lever arms 5216. In furtherembodiments, at least one pair of lever arms 5216 is provided for eachpair of arm segments of the clip portion 5212 or at least one pair oflever arms segments is provided for a plurality or more of pairs of armsegments of the clip portion. Such an arrangement provides sufficientgripping area and force to hold the intervertebral spacer 4800 to theframe at least during formation of the channel and but allows theclinician to relatively easily open up the arms segments to release thespacer.

In further embodiments, the methods of the present invention furtherinclude securing the frame assembly 5200 a to adjacent vertebral bodies2 (FIG. 23C) so that the intervertebral spacer 4800 is disposed in thedistended intervertebral space. Such methods further includedmanipulating the lever arms, for example following drilling or formingof the channel, so the intervertebral spacer 4800 remains disposed inthe distended intervertebral space after the frame assembly is removed.

Referring now to FIGS. 28A-B there is shown another embodiment of anexemplary frame assembly 5200 b according to this aspect of the presentinvention that includes a frame 5202 and a spring clip mechanism 5220.The clip mechanism 5220 includes arm segments 5222 and a manipulatingdevice 5224. The arm segments 5222 are each attached or secured to theframe 5202 on opposing sides of the frame so as to oppose each otherusing any of a number of techniques known to those skilled in the art sothat manipulation of the clip mechanism by a clinician or other medicalpersonnel does not result in the detachment of the clip mechanism. Also,the arm segments 5222 are attached or secured to the frame 5202 usingany of a number of techniques known to those skilled in the art so thatthe process for forming the channel, including drilling of such achannel in the intervertebral spacer 4800, does not result in thedetachment of the clip mechanism or release of the intervertebralspacer. The arm segments 5222 are made of any of a number ofbio-compatible materials, such as stainless steel and/or plastic, thatare appropriate for the intended use (e.g., compatible with the materialof the frame) and can be attached or secured to the frame 5202.

The manipulating device 5224 is removably attached to the frame 5202,more particularly the interior of the frame. In addition, when removablyattached to the frame, the manipulating device 5224 is disposed proximalto and above the intervertebral spacer and extending between the armsegments. In use the surgeon manipulates the lever arms 5226 therebycausing the arm segments 5222 to move away from each other and therebyrelease the intervertebral spacer 4800. In particular embodiments, alateral segment 5225 extends between a plurality of pairs of lever arms5226 and the manipulation of the lever arms 5226 causes the manipulationdevice lateral segment 5225 to urge the arm segments outwardly.

In further embodiments, the clinician or other medical personnel alsocan manipulate the manipulation device 5224 to detach the manipulationdevice from the frame. In this way, the intervertebral spacer 4800 canbe inserted through the frame interior and secured in place when themanipulation device 5224 is thereafter inserted and secured to theframe.

Such an arrangement provides sufficient gripping area and force to holdthe intervertebral spacer 4800 to the frame at least during formation ofthe channel and but allows the clinician to relatively easily open upthe arms segments 5222 to release the intervertebral spacer. Also, asthe arms segments 5222 and the manipulation device 52224 are removablyattached or secured to the frame, a clinician can select arm segmentsand manipulations devices that are appropriate sized for locating aspacer in the intervertebral space for a given target site and apatient's particular physiology.

In further embodiments, the methods of the present invention furtherinclude securing the frame assembly 5200 b to adjacent vertebral bodies2 so that the intervertebral spacer 4800 is disposed in the distendedintervertebral space. Such methods further included manipulating thelever arms 5226, for example following drilling or forming of thechannel, so the intervertebral spacer 4800 remains disposed in thedistended intervertebral space after the frame assembly is removed.

Referring now to FIGS. 29A-B there is shown another embodiment of anexemplary frame assembly 5200 b according to this aspect of the presentinvention that includes a frame 5202 and a spring clip mechanism 5220.The clip mechanism 5220 includes arm segments 5222 b and a manipulatingdevice 5224. Reference shall be made to the discussion regarding FIGS.28A-B for details of features in common with this embodiment and nototherwise provided below.

The arm segments 5222 b are each removably attached or secured to theframe 5202 on opposing sides of the frame so as to oppose each otherusing any of a number of techniques known to those skilled in the art sothat manipulation of the clip mechanism by a clinician or other medicalpersonnel does not result in the detachment of the clip mechanism. Thearm segments 5222 b also are each removably attached or secured to theframe 5202 using any of a number of techniques known to those skilled inthe art so that the process for forming the channel, including drillingof such a channel in the intervertebral spacer 4800, does not result inthe detachment of the clip mechanism or of the intervertebral spacer.The arm segments 5222 b are made of any of a number of bio-compatiblematerials, such as stainless steel and/or plastic, that are appropriatefor the intended use (e.g., compatible with the material of the frame)and can be attached or secured to the frame 5202.

The manipulating device 5224 is removably attached to the frame 5202,more particularly the interior of the frame. In addition, when removablyattached to the frame, the manipulating device 5224 is disposed proximalto and above the intervertebral spacer and extending between the armsegments 5222 b. In use the surgeon manipulates the lever arms 5226thereby causing the arm segments 5222 b to move away from each other andthereby release the intervertebral spacer 4800. In particularembodiments, a lateral segment 5225 extends between a plurality of pairsof lever arms 5226 and the manipulation of the lever arms 5226 causesthe manipulation device lateral segment 5225 to urge the arm segments5222 b outwardly.

In further embodiments, the clinician or other medical personnel alsocan manipulate the manipulation device 5224 to detach the manipulationdevice from the frame. In this way, the intervertebral spacer 4800 canbe inserted through the frame interior and secured in place when themanipulation device 5224 is thereafter inserted and secured to theframe.

Such an arrangement provides sufficient gripping area and force to holdthe intervertebral spacer 4800 to the frame at least during formation ofthe channel and but allows the clinician to relatively easily open upthe arms segments 5222 b to release the intervertebral spacer. Also, asthe arms segments 5222 b and the manipulation device 52224 are removablyattached or secured to the frame, a clinician can select arm segmentsand manipulations devices that are appropriate sized for locating aspacer in the intervertebral space for a given target site and apatient's particular physiology.

In further embodiments, the methods of the present invention furtherinclude securing the frame assembly 5200 b to adjacent vertebral bodies2 so that the intervertebral spacer 4800 is disposed in the distendedintervertebral space. Such methods further included manipulating thelever arms 5226, for example following drilling or forming of thechannel, so the intervertebral spacer 4800 remains disposed in thedistended intervertebral space after the frame assembly is removed.

It should be recognized that the drilling apparatus, methods and systemsof the present invention can be used anteriorally or posteriorally andso that the drill bit of such systems or apparatuses can penetrate orenter the vertebral body through the pedicles.

In addition to securing one or both ends of an arcuate rod or implantdevice in an vertebrae 2 it also is contemplated and thus within thescope of the present invention to secure the arcuate rod within a spacerthat is disposed between adjacent vertebrae. Such securing can be doneas an alternative to securing one or both ends of the implant device orin addition to such securing of the ends.

Additionally, and referring now also to FIG. 31, an arcuate rod orimplant device 1800 is additionally configured to include one or morereceiving apertures 1802 that is/are located so as to be positionedbetween the adjacent vertebral bodies 2 when the arcuate rod or implantdevice is disposed in the adjacent vertebral bodies. The one or morereceiving apertures 1802 also are arranged to receive therein a piningmember 1820 and also so as to engage the pining member so as to therebysecure the pining member relatively to the arcuate member 1800. Suchmechanically engaging includes, but is not limited to threadedconnections, snap-fit type of connections or any other connections knownto those skilled in the art and otherwise appropriate for the intendeduse.

In use, after the arcuate member or implant device 1800 is disposed inthe adjacent vertebral bodies and the intervertebral spacer 4800 isdisposed in the intervertebral space, the pining member 1820 is insertedthrough the intervertebral spacer and secured to the arcuate member orimplant device. It is contemplated and thus within the scope of thepresent invention to provide or form a preformed aperture in theintervertebral spacer 4800 through which the pining member 1820 passes.In this way, the pining member 1820 in combination with the arcuate rodor implant device 1800 secures the intervetebral spacer 4800 between,and to, the adjacent vertebral bodies 2. Although the foregoing refersto an intervetebral spacer, it is within the scope of the presentinvention, for the pining member 1820 and arcuate rod or implant device1800 to be used with any of a number of cages, spacers or other devicesknown to those in the art or hereinafter developed that is/are disposedbetween adjacent vertebral bodies 2.

Referring now to FIG. 30A, there is shown one illustrative embodiment inwhich an arcuate rod or implant device 1000 a that is configured so asto include one or more re-positional elements or wings 1002 and a spacer1050 a including one or more recesses or pockets 1052 that is configuredto receive each of the one or more wings 1002 therein. The implantdevice 1002 also is configured such that the wings 1002 are moveablydisposed within the implant device such that the wings do not generallyextend beyond the outer circumference of the implant device therebyallowing the implant device to be inserted into the arcuate passagesformed in the adjacent vertebrae. The wings 1002 and the implant devicealso are configured such that when the wings are disposed within thepocket(s) 1052 in the spacer 1050 a, the wings extend outwardly from theimplant device and into the pocket(s). In an exemplary embodiment, thewings 1002 are pivotably secured to the implant device and are actedupon by a resilient member (e.g., a spring like element) to cause thewings to be displaced outwardly. In this way the wings 1002 becomesecured in the pocket(s) 1052 and thereby secured within the spacer 1050a.

Referring now to FIG. 30B, there is shown another illustrativeembodiment in which an arcuate rod or implant device 1000 b that isconfigured so as to include one or more dimples, bumps 1004 or othersurface artifacts and a spacer 1050 b including one or more recesses orpockets 1052. In particular embodiments, the implant devices 1000 bincludes a plurality or 3 or more such bumps 1004 that are arrangedabout the circumference of the implant device. The one or more bumps1004 also are configured and arranged so that the bumps are ininterference fit with the inner wall 154 of the passage through thespacer 1050 b. In alternative embodiments, the inner wall 154 furtherincludes one or more depressions in the inner wall in which are receiveda bump 1004.

Referring now to FIG. 30C there is shown another illustrative embodimentin which an arcuate rod or implant device 1000 c is secured within aspacer 1050 c by means of a screw or other device. In use, after theimplant device 1000 c is positioned within the spacer and adjacentvertebrae, the clinician would screw the screw 1060 through the spacersuch that at least the tip 1061 or a portion proximal the tip isreceived in the implant device. In particular embodiments, the spacer1050 c includes a passage 1056 extending from the exterior to the innerwall 1054 of the spacer, the passage can be threaded to receive thescrew 1060 or be a smooth bore. In further particular embodiments, theimplant device includes an opening or depression 1006 in which isreceived the tip 1061. Although a screw with a pointed tip isillustrated, this is not limiting as other types of screws or bolts arecontemplated for use with the spacer 1050 c and implant device 1000 c.

Referring now to FIGS. 32A-B there are shown various views of an arcuaterod or implant device, cap and screw assembly 3800 according to oneillustrative embodiment of the present invention, where the arcuate rodor implant device 800 is shown in cross-section. Reference also shouldbe made to the foregoing discussion regarding FIGS. 15-16 for featureshaving common reference numerals (e.g., the arcuate rod or implantdevice 800 and the screw 804). In the illustrated embodiment, a capmember 3820, 3830 is provided at each end of the arcuate rod or implantdevice 800, which in combination with the screw 804 secures that end andthereby the arcuate rod or implant device to a vertebral body.

In the illustrated embodiment, two different type of cap members3820,3830 are shown; however, this shall not be considered as alimitation. For example and as shown in FIG. 32C, an arcuate rod orimplant device, cap and screw assembly 3800 a according to anotherembodiment is arranged so the same type of cap member 3830 is providedat each end of the arcuate rod or implant device 800. Thus, it iscontemplated and within the scope of the present invention for differenttype cap members or the same type of cap member to be provided at eachend of the arcuate rod or implant device 800.

Referring now to FIGS. 33A-F, there is shown one of the illustrated capmembers, cap member 3820, The cap number 3820 includes an upper portion3822 a and a lower portion 3822 b which is secured to, or formed with,the upper portion so as to extend along an arcuate path from the firstportion. This arcuate path is such that the curvature of the lowerpotion essentially matches that of the arcuate rod or implant device 800so that the lower portion can be received in the lumen of the arcuaterod or implant device. As shown in FIGS. 33C-D, the lower portion 3822 balso is curved to match the left or right hand direction of the arcuaterod or implant device. Inparticular imbodiments the lower portion 3822 bis sized so as to limit or substantially prevent lateral movement of thelower portion in then lumen.

The upper portion 3822 a is generally sized and arranged so as to form aflange like structure 3821 that extends outwardly so the flange likestructure at least rests upon the end of the arcuate rod or implantdevice 800. In further embodiments, the radius of the flange likestructure 3821 such that the upper portion does not generally extendbeyond the region defined by the end of the arcuate rod or implantdevice.

The upper portion 3822 a includes a stepped through aperture 3824 thatis coupled to and communicates with a through aperture 3826 provided inthe lower portion 3824 b. The stepped through aperture 3824 and lowerportion through aperture 3826 are arranged so the threaded portion 805 bof the screw 804 extends downwardly and in a direction that allows thethreaded portion to exit from the arcuate rod or implant device 800 andthereby be secured to the vertebral body 2 (e.g., such as that shown inFIG. 24C). The stepped through aperture 3824 also is formed so that thehead 805 a of the screw 804 should contact a contact surface 3823; thuslimiting the motion of the screw. In further embodiments, the steppedthrough aperture 3824 including the contact surface 3823 are arranged soas to compliment the shape of the head 805 a of the screw 804. Forexample, the stepped through aperture and contact surface form a dishedshaped structure such as that illustrated in FIG. 34D.

Referring now to FIGS. 34A-G, there is shown another illustrated capmembers 3830. The cap member 3830 includes an upper portion 3832 a and alower portion 3832 b that is secured to, or formed with, the upperportion so as to extend along an arcuate path from the first portion.See also the discussion above regarding the lower portion of 3822 b forfurther details.

The upper portion 3832 a includes a flange like structure 3831 and araised section 3833 that extends outwardly from a surface of the flangelike structure. The flange like structure 3831 is generally sized andarranged so it extends outwardly so at least a portion of the flangelike structure extends beyond the end of the arcuate rod or implantdevice 800 and extends over, and thus adjoins or rests upon, a surfaceof the vertebral body (such as for example that illustrated in FIGS.35A,B). In further embodiments, the flange like structure 3831 forms anelliptical shape, whose long or major axis is arranged so as to be at apredetermined angle with respect to the arcuate rod or implant device.The predetermined angle is such that the portion of the flange likestructure along the long or major axis of the elliptical structure ispositioned so the one or more downwardly extending spikes 3838 are in adesired location with respect to the vertebral body 2. In exemplaryembodiments the flange like structure 3831 is arranged so the major orlong axis is substantially perpendicular to the arcuate rod or implantdevice 800.

The raised section 3833 of the upper portion 3832 a is generallyarranged to receive the screw 804, in particular the head 805 a thereof.The upper portion 3832 a including the raised portion 3833 and theflange like structure are arranged so as to include a stepped throughaperture 3834 that is coupled to and communicates with a throughaperture 3836 provided in the lower portion 3832 b. The stepped throughaperture 3834 and lower portion through aperture 3832 b are arranged sothe threaded portion 805 b of the screw 804 extends downwardly and in adirection that allows the threaded portion to exit from the arcuate rodor implant device 800 and thereby be secured to the vertebral body 2(e.g., such as that shown in FIG. 24C). The stepped through aperture3834 also is formed so that the head 805 a of the screw 804 shouldcontact a contact surface 3833; thus limiting the motion of the screw.In further embodiments, the stepped through aperture 3834 including thecontact surface 3833 are arranged so as to compliment the shape of thehead 805 a of the screw 804. For example, the stepped through apertureand contact surface can form a dished shaped structure such as thatillustrated in FIG. 34D.

As indicated above, one or more spikes 3838 extend downwardly from theflange like structure 3831 from a surface there of that opposes thevertebral body 2. The spikes 3838 are sized and arranged so as to engageat least the hard bony structure of the vertebral body 2 (e.g., corticalbone of the vertebral body). In this way, the engagement of the spikes3838 with the cortical bone also fixes the rod with respect to thevertebrae. In more particular embodiments, a plurality of spikes extenddownwardly. In exemplary embodiments, four spikes extend downwardly fromthe flange like structure, the spikes being arranged so that there aretwo spikes along each of the ends of the flange like structure andspaced from each other such as shown in FIG. 34B.

Although the spikes 3038 are illustrated as cylinders with a pointedend, this is not limiting as the spikes may comprise any other structureknown in the art that provides a similar effect or function. Withoutbeing bound by any particular theory, the above described cap member3820, 3830 when secured to the vertebral body 2 as described above isexpected to create a structure that prevents the screw 804 from rotatingor creating a windshield wiper effect within the cancellous bone of avertebral body 2.

Referring now to FIGS. 35A-B there is shown various illustrativeaxonometric views of adjacent vertebral bodies 2 that illustrates yetanother arcuate rod or implant device, cap and screw assembly 3800 baccording to yet another illustrative embodiment of the presentinvention, where the arcuate rod or implant device is shown incross-section. The arcuate rod or implant device, cap and screw assembly3800 b according to this embodiment includes a cap member 3840 which isprovided at one end of the arcuate rod or implant device 800, althoughit is within the scope of the present invention for such a cap member tobe provided at both ends of the arcuate rod or implant device.

Such a cap member 3840 includes an upper portion 3842 a and a lowerportion 3842 b. The upper portion 3842 a includes a flange likestructure 3831 and a plurality of raised sections 3843 a-c that extendoutwardly from a surface of the flange like structure. The flange likestructure 3841 extends substantially in one direction at an angle withrespect to the arcuate rod or implant device 800.

The raise sections 3843 a-c are arranged on the flange like structure sothat a first raised section 3843 a, the flange like structure 3841 andthe lower portion 3842 b cooperate as described above in regards to thediscussion for FIGS. 34A-G so that a screw 804 passes therethrough andthrough the arcuate rod or implant device. Thus, reference shall be madeto the foregoing discussion of FIGS. 34A-G for further details.

Each of the other of the plurality of raised sections 3843 b,c and theflange like structure 3841 are configured so as to provide a steppedthrough aperture to receive a screw 804 therein. Reference shall be madeto the foregoing discussion for FIGS. 34A-G as to the details of such astepped through aperture. Also, each of the other of the plurality ofraise sections 3843 a,b are spaced from the first raised section 3843.In particular embodiments, these other raised sections 3843 b,c arelaterally disposed with respect to, and on opposite sides of, the firstraised section 3843 a. In use, a screw 804 is passed through the steppedaperture in each of these other raised sections 3843 b,c and is screwedinto the vertebral body 2 until the head 805 a of the screw 804 contactsthe contact surface of the stepped through aperture. In this way, eachof these laterally disposed screws as well as the screw passing throughand secured to the first raised section 3843 a thereby further fixatesthe cap member 3840 and thus the arcuate rod and implant device 800 tothe vertebral body.

Although a preferred embodiment of the invention has been describedusing specific terms, such description is for illustrative purposesonly, and it is to be understood that changes and variations may be madewithout departing from the spirit or scope of the following claims.

It should be clear that the methods, systems, and devices of theinvention are not limited to securing a pair of vertebrae, but ratherany combination of multiple vertebrae segments. It also should be clearthat the methods, systems, and devices of the present invention are inno way limited to vertebrae segments. In particular, the inventionenables securing any solid substrates, particularly bone substrates,without use of protruding screws or plates. It also should be understoodthat the invention is applicable to a wide variety of fixationconfigurations, including bone-to-bone with a gap; bone-to-bone withouta gap; bone-to-bone with bony spacers; and bone-to-bone with a non-bonyspacer such as a metal, polymer, or a biodegradable material.

INCORPORATION BY REFERENCE

All patents, published patent applications, US patent application andother references disclosed herein are hereby expressly incorporated byreference in their entireties by reference.

EQUIVALENTS

Those skilled in the art will recognize, or be able to ascertain usingno more than routine experimentation, many equivalents of the specificembodiments of the invention described herein. Such equivalents areintended to be encompassed by the following claims.

The invention claimed is:
 1. A method for forming a plurality ofchannels in a treatment or surgical site of one or more segments of abony structure or adjacent vertebra of a spine, said method comprisingthe steps of: positioning a frame assembly proximal one location of thetreatment or surgical site; securing the frame assembly to adjacentsegments of the one or more segments of a bone or bony structure oradjacent vertebra; providing a pivot arm assembly which includes a pivotarm and a pivot pin bracket operatively coupled to the pivot arm;removably attaching the pivot arm assembly to the frame assembly bysliding the pivot pin bracket into the frame assembly for engagementwith the frame assembly; operatively coupling a drill bit to the pivotarm and rotating the pivot arm and drill bit about a pivot point infixed relation to the frame assembly to form one of the plurality ofchannels in the surface or sub-surface of the bone, bony structure orvertebra, wherein the frame assembly being provided further includes aframe having a plurality of through apertures, each through apertureincluding a constricted portion and a plurality of securing members andwherein said securing further includes driving each of the plurality ofsecuring members through the through apertures and the constrictedportion and into the bone, bony structure or vertebra at the site,whereby the frame is secured in fixed relation to the bone, bonysegments or vertebra by the engagement of the constricted potion withthe securing member; repositioning the frame assembly proximal toanother location of the treatment or surgical site; and repeating saidsteps of securing, removably attaching, and rotating at said anotherlocation.
 2. The method of claim 1, wherein the frame is secured infixed relation by the lateral stiffness of the securing members.
 3. Themethod of claim 1, further comprising: providing a drill assemblyincluding a drill bit; attaching the drill assembly to the frameassembly so the drill bit follows a predetermined path in fixed relationwith respect to the frame assembly; and moving the drill bit through thepredetermined path while the drill bit is rotating thereby cutting thechannel with the drill bit.
 4. The method of claim 1, further comprisingthe steps of: providing a pivot arm that rotates in fixed relation tothe frame assembly; operatively coupling a drill bit to the pivot arm sothe drill bit follows a predetermined path in fixed relation withrespect to the frame assembly as the pivot arm is rotated.
 5. The methodof claim 4, further comprising the step of rotating the drill bit whilerotating the pivot arm thereby cutting the channel with the drill bit.6. The method of claim 4, further comprising the step of determining ifthe movement of the drill bit in a first direction formed one of acomplete channel or a partial channel and in the case where it isdetermined that a partial channel was formed, detaching and re-attachingthe drill assembly so as to be moveable in a second direction that isdifferent from the first direction and moving the drill bit in thesecond direction.
 7. The method of claim 5, further comprising the stepof determining if the rotation of the pivot arm in a first directionformed one of a complete channel or a partial channel and in the casewhere it is determined that a partial channel was formed, detaching andre-attaching the pivot arm so as to be rotatable in a second directionthat is different from the first direction and rotating the pivot arm inthe second direction.
 8. The method of claim 1, further comprising thestep of: locating an implant in the channel.
 9. The method of claim 8,further comprising the step of: attaching the implant within the channelto the bone, bony structure or vertebras, wherein said attachingincludes securing the implant to the bone, bony structure or vertebrausing a plurality or more of securing devices.
 10. The method of claim8, further comprising the step of: providing a dynamized implant device;and wherein said locating an implant includes locating the provideddynamized implant device in the channel.
 11. The method of claim 10,wherein the provided dynamized implant device comprises a plurality ofmembers that are arranged so as to allow relative movement between theplurality of members along a common axis and to restrain movement inother directions.